Science Stars Chemistry Issue by Science Stars Magazine

CHEMISTRY ISSUE 2021

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FEATURES

1 1 1 1 2 2 2 2 3

an introduction to chemistry

the science of sanitisers

welcome to the chem lab

meet Dr Rehana Malgas–Enus

more about metals

how food is linked to science

DIY EXPERIMENTS TO TRY

DOWNLOAD THESE CHEMISTRY APPS

0 the STUDY TIPS YOU NEED

06 18

REGULARS

6 3 3 3 3 3 3

COVER STORY

AVAILABLE BURSARIES

QUIZ

PUZZLES

ANSWERS

FACTS

SCIENCE CENTRE

team Science Stars

LETTER FROM THE EDITOR

Editor • Shani Tsai Graphic designer • Stacey Swartz

You’ve got this! If there’s anything that the word “love” brings to mind, it’s chemistry – we all yearn to be admired and appreciated. Many people find themselves being drawn to these positive feelings, and it may even motivate them to spread the love. If you think about it, learning isn’t much different. The more time you spend paying attention to what you’re learning and the ways in which you choose to hone your skills all determine how well you do when it comes to tests and assignments. And when we excel in something, it makes us more excited to keep doing it. In this issue, we focus on chemistry – from possible careers in the field (page 6), to must-know lab rules on page 16 and tips that’ll make for a healthy study routine (page 30). Last year had its fair share of challenges – schooling was disrupted, we had to adapt to a new normal and we all dealt with the unexpected loss of family members and friends … but we’re all in this together.

Contributing writers • Zakiyah Ebrahim • Nicole Ludolph • Chireez Fredericks • Lusanda Tamesi • Mukosi Fulufhelo Chairman • Madambi Rambuda Ambassador • Prof. Azwindinni Muronga Sales & Marketing Rep • Ntombizanele Thangayi

Subscriptions • info@sciencestars.co.za Copyright 2020 Science Stars Pty Ltd. All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or any means, electronically or mechanically, without prior permission. Science Stars is published by Science Stars Pty Ltd

Turn to page 29 for mobile apps that can help you understand your work easier, depsite not having daily access to your classroom and teachers. Good luck with the academic year – with hard work and dedication, we know you’ll make it!

Shani Tsai Editor

1 Bridgeway, Century City, Cape Town, 7441 021 830 5200 info@sciencestars.co.za www.sciencestars.co.za

COVER FEATURE

BUILDING CHEMISTRY WITH CHEMISTRY FANCY A CAREER IN THE FIELD? THERE IS A WORLD OF ENTICING CAREER POSSIBILITIES THAT AWAITS. By: Zakiyah Ebrahim

Science Stars Chemistry Issue | www.sciencestars.co.za

COVER FEATURE

here are chemistry inventions that have enabled

Turn your day dream into a day job someday

the modern world and, more importantly, saved

Wits explains that chemistry qualifications are important in

lives. So of these inventions include the (accidental)

jobs involving physics, biochemistry, zoology, botany, geology,

discovery of polythene (the most common plastic object)

pharmacology and medicine. We take a look at some of the

and the production of penicillin, a group of antibiotics used

roles related to chemistry and what exactly they entail.

to treat bacterial infections. As of 2016, penicillin has saved 200 million lives since its first use as a medicine in 1942,

Career options

according to BBC.

Analytical chemist Analytical chemists perform basic laboratory research and

We take a look at a few career options and give you top tips

process and product development; design instruments used in

from people whose job roles and careers involve chemistry on

analytical analysis; teach; and even work in marketing and law,

how you can build a life you love with it.

explains the American Chemical Society (ACD).

What is chemistry all about?

They solve problems in many areas of chemistry and for all

Chemistry deals with matter and how it changes, as well

kinds of industries. Examples include analytical chemists

as the production and use of energy. It is applied in several

using their measurements to assure the safety and quality of

different areas of industry, commerce and education, so the

food, pharmaceuticals, and water; to assure compliance with

opportunities appear almost endless. Bear in mind that

environmental and other regulations; to support the legal

studying chemistry will not restrict you to a career in a

process; and to help physicians diagnose diseases.

laboratory. Instead, it can lead to many different careers across a wide range of sectors. Careers incorporating its use sees the

Pharmacologist

manufacturing of domestic products, fertilisers, explosives, and

Pharmacologists research and understand chemical processes

the preparation of medicines, among many others.

so that they can create, develop, and test new medications.

According to the University of the Witwatersrand’s faculty of

As a pharmacologist, you can work for pharmaceutical

science, companies that hire chemists (a person engaged in

manufacturers on the industry and commercial side of the field,

chemical research or experiments) include: • chemical manufacturers • cosmetics and fragrance producers • pulp and paper manufacturers • pharmaceutical companies • food and beverage producers • mining and metallurgy companies • oil and gas companies • plastics and polymer manufacturers

or you can fulfil a teaching or research role role university in

are harmful to either humans or the environment, explains

•

engineering firms, and many more.

teaching or research. Additionally, pharmacologists can work in labs, such as a research lab or crime lab. Environmental consultant If you have a passion for both the environment and chemistry, then this might be the career to pursue as you will work on establishing whether materials which organisations use EduConnect, adding that environmental consultants work

However, if none of the above interests you, Wits goes on

with management to provide solutions in eliminating the

to explain that there are also several other opportunities.

employee’s exposure to harmful chemicals and substances.

These are at universities, colleges and schools, government agencies, hospitals and medical organisations, environment

Forensic toxicologist

and pollution control bodies, consulting firms and national

As described by Crime Scene Investigator EDU, forensic

scientific research and development councils.

toxicologists perform tests on bodily fluids and tissue samples to during autopsies to look for the presence of chemicals

What you’ll need

identify any drugs or chemicals present in the body. They go on

Pursuing a career in chemistry will require a personal checklist

to say: “Forensic toxicology combines toxicology with similar

of scientific and mathematical aptitude; a willingness to work

disciplines, including clinical chemistry and pharmacology,

hard; attention to detail; perseverance; and a deep interest in

to aid in the investigation of deaths surrounding poisoning

the world of chemistry.

(accidental or intentional) or drug use. Science Stars Chemistry Issue | www.sciencestars.co.za

COVER FEATURE

Developing a love for chemistry If you think you’ve got what it takes to enter this fascinating field but aren’t quite convinced it could keep you happy, we’re confident we can sway you over with these encouraging words from people who have first-hand experience in the field. Leading a lab analysing animal feed sources Ulrich Fritz is currently employed by the Western Cape Department of Agriculture as a Scientific Technician-Nutrition and Product Quality within the Animal Sciences Directorate. He leads the staff and laboratory that is charged with analytical analyses on various animal feed sources. Fritz explains: “Our analyses is based on standard, documented laboratory methods. In summary, the results of our analysis are used for dietary formulations as well as providing us with nutritional knowledge. In this manner we are able to make educated recommendations for optimal feeding of our livestock.” Fritz told Science Stars that his love for the agricultural profession is catalysed by the fact that agriculture serves as the backbone of the Western Cape economy: “A thriving agricultural sector inevitably means a thriving economy for the province.” To pursue any scientific career, pure mathematics and the sciences are non-negotiable, says Fritz, and adds: “To give yourself that extra boost in Matric, consult exam papers of previous years, form study groups, consult your educator if

Ulrich Fritz

you have any uncertainties, attend summer schools that are so often offered by different tertiary institutions and attempt to attend any math/scientific type of extra mural aid. The world is your oyster – if you have an enquiring mind, this

Through samples forensic toxicologists determine which toxic

career can be rewarding and satisfying,” he says.

substances are present, in what concentrations, and the effects of the substances on the body.”

Chemistry teacher Tracey Henry is a high school chemistry teacher and believes

Chemical engineer

that she has the world’s most precious resource in her care,

A career in chemical engineering is all about transforming

saying that the planet’s future depends on how she inspires

raw materials into useful, everyday products, explains The

the mind of a child.

Guardian, who goes to say “the clothes we wear, the food and drink we consume and the energy we use all depend upon

“Children will grow to either protect the planet or they will

chemical engineering.”

not care for it at all, and the understanding and study of chemistry helps us understand how to protect ourselves and

As a chemical engineer, you will figure out the processes to

the planet. Without the consumption of the correct atoms

make all these products, while also helping to ensure health

found in food, for example, our bodies will become sick and

and safety standards are met.

even die. The magical, invisible forces that hold one atom

Science Stars Chemistry Issue | www.sciencestars.co.za

COVER FEATURE

together or molecules together, hold our earth together and connect us to the entire universe.” Henry also has some valuable suggestions for developing a love for chemistry at high school level: “Students have the perception that science is difficult, but it’s not. It simply requires consistent and determined effort. It teaches you to persevere and to be positive and hopeful when you feel like you may not succeed. You may fail at solving a problem, but failure allows you to remember the steps to solve a similar problem in the future. Learners who make mistakes show greater improvement in final exams because they were forced to think more deeply. Chemical engineer Obtaining a Bachelor of Science and a Master of Science in Chemical Engineering at the University of Cape Town has allowed Jacobus van der Merwe to form part of strategic exercises which aim to localise manufacturing, as well as

Tracey Henry

electrical power generation technology in Africa. “This presents the continent with the opportunity to realise the socio-economic benefits associated with the manufacture of chemicals and related components along with electrification for itself, rather than relying on imports,” he explains. What Jacobus enjoys most about his job is to see chemical plant equipment designs evolve from a conceptual stage to final construction and commissioning, as well as to witness how newly constructed plants or equipment serve researchers and engineers. “To learners who are interested in pursuing chemical engineering but aren’t 100% persuaded: If you enjoy technology, maths, chemistry and physics, a qualification in chemical engineering will pave the way to a fulfilling and rewarding career,” he adds.

Jacobus van der Merwe

Science Stars Chemistry Issue | www.sciencestars.co.za

It’s what we build

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We all dream of a better future. For ourselves, our families and our country. SANRAL, as part of the National Development Plan, is improving and expanding vital road infrastructure. In the process we are creating jobs, transferring skills and developing opportunities for all South Africans. We are proud to be a part of the National Development Plan, because we know that roads are more than just roads, they pave the way to a better future.

More than just roads

BRANCHES

AN INTRODUCTION TO… CHEMISTRY AND ITS BRANCHES OPTIONS ARE ENDLESS IN THE FIELD. WE TAKE YOU THROUGH THE TOP FIVE BRANCHES. By: Zakiyah Ebrahim Chemistry is the subdiscipline of science that deals

explains Live Science. Taking medication or diluting

with the composition of matter and the physical and

concentrated juice is also other ways in which we

chemical characteristics associated with different

incorporate chemistry into our regular lives.

material objects. "Everything you hear, see, smell, taste, and touch involves chemistry and chemicals (matter),"

Here’s a look at the various branches…

according to the American Chemical Society (ACS), a non-profit science organisation for the advancement

ORGANIC CHEMISTRY

of chemistry.

Organic chemistry is the study of carbon compounds, as well as the chemicals in living organisms. The

"And hearing, seeing, tasting, and touching all involve

process of photosynthesis in a leaf is considered

intricate series of chemical reactions and interactions

organic chemistry, as there is a change in the

in your body," the NPO explains. Think of it this way:

chemical composition of the living plants.

we’re all doing chemistry, or something that involves chemistry, pretty much in everyday life – even if you’re

Substances that are primarily made up of carbon

not a chemist.

and hydrogen (C-H) bonds are considered organic. According to ThoughtCo., this branch of

Cooking involves chemistry, and so does using

chemistry is significant as it is the study of life and

cleaning detergents to wipe off our counters,

all of the chemical reactions related to life, and plays

Science Stars Chemistry Issue | www.sciencestars.co.za

INTRO

a part in the development of common household chemicals such as fuels, plastics, food additives and drugs (in medicine). They explain that several careers apply an understanding of organic chemistry, including chemical engineers, chemists, veterinarians, dentists, doctors and pharmacologists. Organic chemists synthesise new chemicals for pharmaceutical companies and find novel applications for them.

Organic vs inorganic The key difference between organic and inorganic compounds is that all organic compounds contain carbon, while the majority of inorganic compounds do not contain carbon. INORGANIC CHEMISTRY Inorganic chemistry covers inorganic compounds. In other words, it is the study of elements and compounds that do not contain the C-H bond, such as metals, minerals and organometallic compounds. Inorganic compounds are used as catalysts, coatings, pigments, medicines and more. They often have high melting points and particular high or low electrical conductivity properties, which make them beneficial in certain circumstances.

Science Stars Chemistry Issue | www.sciencestars.co.za

INTRO

For example, ammonia, which is a nitrogen source in

as insulin for those living with diabetes).

fertiliser, is one of the key inorganic chemicals used in the production of fibres, nylons, polyurethanes

ANALYTICAL CHEMISTRY

(used in adhesives and foams), and hydrazine (used

If we’re going to perform experiments, we have to

in jet and rocket fuels), among others, explains

ensure they’re done correctly and efficiently. That’s

ACS. Chlorine (Cl) is another example, and is used in

where analytical chemists come in: they analyse the

the manufacturing of polyvinyl chloride (for pipes),

chemical components and can tell you how much of it

clothing and furniture.

exists in a sample.

According to ACS, inorganic chemists are employed in

Analytical chemistry is also used in forensic science

fields ranging from mining to microchips.

and environmental science, and can be further divided into two main branches: qualitative (using methods

Important note

and measurements to determine the components of

Although organic chemistry is the study of carbon-

substances) and quantitative analysis (how much of

containing compounds and inorganic chemistry the

each component is present in a substance). If you

study of the remaining subset of compounds, there is

have an unidentified sample, analytical chemistry

an overlap between the two.

will employ these methods to help identify what the sample is.

BIOCHEMISTRY Biochemists focus on biology. Since everything in

Have you ever considered something as intricate as

the body is composed of atoms and molecules of

how much caffeine is in a cup of coffee? This is what

various chemical compounds, biochemists study these

analytical chemists can investigate. Analysing drugs

chemical processes in living organisms.

present in athelete’s urine samples and determining the pH level of a swimming pool, for instance, can also

Biochemistry can be subdivided into different

be answered by an analytical chemist.

disciplines, including: • Enzymology (the study of enzymes),

NUCLEAR CHEMISTRY

• Endocrinology (the study of hormones),

This branch of chemistry studies radioactivity, and

• Clinical biochemistry (the study of diseases),

deals with the nuclear properties of, and the chemical

• Molecular biochemistry (the study of biomolecules

processes in, radioactive substances.

and their functions). However, the field has become very interdisciplinary According to Future Learn, biochemists' expertise is

in its applications over the years. Chemists, geologists,

used to tackle a huge variety of problems on a day-to-

physicists, and engineers all employ aspects of nuclear

day basis. Some examples include the discovery and

chemistry in their careers. This can be explained

improvement of drugs (used in medicine); compounds

by looking at examples, such as the study of the

that are used in (bio)chemical industries (like cleaning

formation of elements in the universe, and the design

products and detergents) and DNA recombinant

of radioactive drugs for diagnostic medicine – two

technology (used to make important molecules such

very different aspects of nuclear chemistry.

Science Stars Chemistry Issue | www.sciencestars.co.za

SANITISERS

MORE ABOUT SANITISERS HOW DO ALCOHOLBASED HAND SANITISERS WORK AGAINST COVID? By: Mukosi Fulufhelo

lcohol is a good solvent. This means it can dissolve other

that are recommended by health authorities as both safe and

substances. When it comes to the coronavirus, It dissolves

effective for use by humans. Other alcohols may be effective,

its outer protein layer, rendering the virus dead. However,

but detrimental to your health, and some, just detrimental like

can we use any alcohol to make hand sanitisers? How about the

methyl alcohol.

alcohol we drink? Is it effective? If so, why not use it to kill off the virus completely?

Ethyl alcohol

Well, let’s look at the makeup of sanitisers, and some chemistry to help us understand. What are hand sanitisers made up of? It is important to know the ingredients in each product you use. This helps you avoid using products with ingredients you may be allergic to or chemicals that are bad for your health. For hand sanitisers, WHO recommends two basic formulas: (1) 80% ethanol (ethyl alcohol), 1.45% glycerol, and 0.125% hydrogen peroxide, and distilled or boiling water Ethyl alcohol, also known as grain alcohol, is a 2 carbon-chained (2) 75% 2-propanol (isopropyl alcohol), 1.45% glycerol, 0.125%

alcohol molecule. This is alcohol that we consume in alcoholic

hydrogen peroxide, and distilled or boiling water..

beverages. We can only take in up to 43% of this. Hand sanitisers must have a very high concentration of alcohol to be effective.

Getting to know the alcohols

This is why we can not drink alcohol to destroy the covid virus

Ethyl and isopropyl alcohol are used as active chemicals in hand

completely. Alcohol in hand sanitisers is adulterated to keep

sanitisers as recommended by the FDA. The key structural feature

people from drinking it. Adulterating may be done using foul-

of these alcohols is that they are short carbon-chained, making it

tasting, toxic, or non-toxic chemicals. Trouble is, you will not be

easy for them to disrupt the structures of viruses and microbes.

able to identify the chemical used to denature the alcohol from

Ethyl and isopropyl alcohol are currently the only two alcohols

checking the labels, so DO NOT consume hand sanitisers.

Science Stars Chemistry Issue | www.sciencestars.co.za

TRENDING TOPIC SANITISERS

Isopropyl alcohol

Lipid bilayer structure

Isopropyl alcohol, also known as rubbing alcohol, is a threecarbon-chained alcohol molecule. It is not suitable for human consumption. This toxic alcohol will damage your nervous system and internal organs if you drink it. However, it doesn't

Coronavirus model picture

get absorbed through the skin that is why it is safe to use in hand sanitisers. How do these alcohols fight Covid? Both ethyl alcohol and isopropyl are soluble in water. Generally, carbon chains (saturated with hydrogens) give a molecule hydrophobic (water-fearing) characteristics, making it less soluble in water. However, in the case of ethyl alcohol and isopropyl, the carbon chain is short enough so that the more polar -OH (hydroxyl) group dominates, giving them a polar character. Alcohols with longer carbon chains are less soluble in water.

When the coronavirus is in water, the hydrophobic effect gives

Solubility is important for the molecules to be able to move

the cell membranes its strength. Alcohol can disrupt the water-

across the bilayers of membranes in the body.

loving protein membrane of the virus, effectively destroying the entire structure of the virus. This is essentially all you need to kill

The short carbon nature of these two also make them slightly

a virus.

lipophilic (lipid-loving) so it can also penetrate the lipid bilayers of biological membranes. This is how alcohol destroys viruses.

Other ingredients used in hand sanitisers

To understand this better, let us look at the structure of the

Chemicals are added into the formula to make sanitisers less

coronavirus causing covid.

harsh on the skin. Glycerol is an emollient that is used to moisturise skin since alcohol is very drying. Hydrogen peroxide

The coronavirus

is used in low concentrations to help eliminate contaminating

The protective shape of the coronavirus causing covid is made

spores. Other ingredients like polymers can be added to give

up of a lipid bilayer. These layers are pin structured molecules

the gel consistency to hand sanitisers and some essential oils to

whose heads are attracted to water (hydrophilic) and tails are

improve the smell.

repulsed by it (hydrophobic). In a water-rich environment, these lipids arrange themselves such that the tails are protected from the water. This is called the Hydrophobic Effect. See diagram.

It’s good to know ...

• Ethanol is a clean-burning fuel that reduces carbon monoxide and hydrocarbon tailpipe emissions. • It is an oxygenate, and that oxygen allows it to burn more cleanly and more completely than gasoline. • The fuel is made from corn and other crops, renewable resources that derive their energy from the sun, rain and soil. Science Stars Chemistry Issue | www.sciencestars.co.za

LAB

ENTERING THE CHEM LAB WE TAKE YOU THROUGH ALL THE IMPORTANT INFORMATION FOR WORKING IN A LABORATORY. By: Chireez Fredericks What is in a basic chemistry kit?

•

Never leave experiments unattended.

Whether you are trying your hand at chemistry experiments at

•

Never attempt to catch a falling object.

home or under the watchful eye of your teacher, equip yourself

•

Be careful when handling hot glassware and apparatus.

with these items:

•

Never point the open end of a test tube containing a

substance at yourself or others.

•

Durable glass beakers

•

Make sure no flammable solvents or any other

•

Graduated cylinders for measuring liquids

flammable materials are in the surrounding area when

•

A flask

lighting a flame and do not leave a Bunsen burner

•

Wickless alcohol lamp and stand

unattended.

•

Test tubes and test tube rack

•

When not in use, turn off all heating apparatus, gas

• Thermometer

valves and water faucets.

•

Tubing pinch clamp

•

Keep the floor clear of all objects and make sure to

•

Glass tubes

thoroughly clean your laboratory work space at the end

•

Rubber stoppers and

of each session.

•

pH papers

•

Never block exists or access to emergency equipment.

•

Inspect all equipment for damages such as cracks or

What are the safety steps in a chemistry lab?

defects before using them and do not use damaged

Life-threatening injuries can happen a chemistry lab. Use

equipment.

this checklist to ensure you and your class mates are safe at

•

Never pour chemical waste into a sink drain or waste

all times:

basket. Chemical waste needs to be placed in

Science Stars Chemistry Issue | www.sciencestars.co.za

LAB

appropriately labeled waste containers.

Density: Describes how compact a substance is, and is calculated

•

Make sure to always dispose of broken glassware

by dividing mass by volume or D = m/v.

and other sharp objects (like syringe needles) by

immediately placing them in their designated waste

containers.

Electron: A particle of an atom that surrounds the nucleus; has a charge of negative one.

•

Always wear appropriate eye protection such as

chemical splash goggles and disposable gloves, when

Molecule: A type of particle that is made up of two or more

handling hazardous materials.

atoms bonded together; carbon monoxide is an example of

•

Always wear a full-length, long-sleeved laboratory coat

a molecule.

or chemical-resistant apron.

•

Avoid wearing shirts that expose the torso, shorts or

short skirts. Instead, opt for long pants that cover the

legs completely.

Precipitation: A solid substance that can form when certain

•

Wear shoes that adequately cover the whole foot. No

dissolved substances are mixed together.

heels and always choose non-slip soles.

•

Secure long hair and loose clothing; especially loose

Proton: A particle of an atom that is inside the nucleus; has

long sleeves, neck ties, or scarves and remember to

a positive charge.

remove jewellery, particularly pieces that hang loosely.

•

Do not directly touch any chemical with bare hands.

Solubility: Describes how much of a substance dissolves in

•

Check the label to verify it is the correct substance

another substance.

before using it.

•

Keep your hands away from your face, eyes, mouth and

Texture: Describes how the surface of a substance feels (its

body while using chemicals.

roughness, softness, or smoothness).

•

Know the location of and know how to use: fire extin

guishers, alarm systems with pull stations, fire blankets,

eye washes, first-aid kits and deluge safety showers.

Neutron: Located in the nucleus of an atom, has no charge.

Learn the lingo Trying to wade through the murky waters of chemistry terms can get confusing fast. Keep things clear by exploring these common terms in chemistry. Atom: the smallest unit of an element that displays the same properties as the element, for example, hydrogen. Atomic number: The number of protons in the nucleus of an atom; for example, the atomic number for helium is 2. Chemical formula: A short form used to represent a molecule; uses letters and numbers; only pure substances have chemical formulas; H2O is the chemical formula for water. Combustibility: The ability of a substance to catch fire and burn in air. Decomposition: A kind of reactivity that can break down a substance into its parts; for example, water can be broken down into hydrogen and oxygen by decomposition. Science Stars Chemistry Issue | www.sciencestars.co.za

PROFILE

Meet Dr. Rehana Malgas-Enus WE CHAT TO HER ABOUT HER LIFE AND PASSIONS. By: Lusanda Tamesi

leading emerging researcher, bringing science to public

this opens up a wide range of applications, ranging from catalysis

future leaders Dr. Rehana Malgas-Enus (38). Growing up in

to water treatment, to biomedical uses such as cancer.

Mitchells Plain (Beacon Valley) on the Cape Flats, where

dreams are shattered, and poverty makes drugs and gangsterism

Utilising her researching skills to change lives, Rehana started

seem like the only feasible way of living, Rehana beat the odds.

the SU Chemistry Outreach Initiative (SUNCOI), a program that supports learners from disadvantaged schools in physical

Being raised by a single mother who worked at a factory

sciences and mathematics. Without proper laboratories or

encouraged Rehana to reach for what seems like the impossible.

chemicals, learners struggle to complete their physical science

“My mother never had an office job. She worked very hard

(chemistry) experiments, which are a curriculum requirement.

to put my sister and me through school,” said Rehana. This

SUNCOI makes it possible for these learners and their teachers

Stellenbosch University (SU) alumna is a researcher and lecturer in the Department of Chemistry and Polymer Science, where she concentrates in nanotechnology.

“You are not incapable of doing it. You can do it if you give it a try, don’t be afraid” - Dr. Rehana Malgas-Enus

Rehana obtained her BSc Honours

to spend weekends in fully equipped laboratories at SU and complete their designated experiments. Since we are faced with the novel Covid-19 pandemic, the SUNCOI made an initiative to go to the

and Master’s Degree in Chemistry at the Western Cape University

laboratories and record experiments for a better understanding

and her Ph.D. in Inorganic Synthetic Chemistry at SU when she

of the theory of chemistry embedded in the high school

was 28.

curriculum. Rehana believes in practical measures other than theoretical values thus making it her priority to cater to the

She is now a senior lecturer and head of the RME-NANO research

previously disadvantaged communities and compose live-videos

group (established in 2013) at the Department of Chemistry

for these young minds. Rehana said that SUNCOI 2021 Covid-

&Polymer Science at Stellenbosch University. The RME-NANO

19 measures include the goal of providing chemical kits at an

research group focuses on the design and engineering of organic

affordable price making it easier for them to do experiments in

and inorganic nanomaterial, tailored for a specific function, and

their schools.

Science Stars Chemistry Issue | www.sciencestars.co.za

METALS

MARVELLOUS METALS WE TAKE A LOOK AT WHY THESE COMMONLY SEEN METALS ARE WORTH THEIR WEIGHT. By: Zakiyah Ebrahim

Science Stars Chemistry Issue | www.sciencestars.co.za

METALS

Elements may be classified as either metals or non-metals, based

Zinc Chloride

on their properties. However, most of the elements in the periodic

Zinc chlorides exists in nine different crystalline forms that are

table consist of metals. According to the BBC Bitesize, metals have

currently known. They are colourless or white, and are highly

physical properties including:

soluble in water, notes Science Direct. Zinc chloride also exhibits hygroscopic qualities, ed-tech company BYJU’S explains. This

•

high melting points;

means that it attracts and captures the water molecules in

•

good conductors of electricity (like electrical wires);

its environment.

•

good conductors of heat (such as silver and copper);

•

high density;

Wood furniture is often coated with zinc chloride to prevent

•

malleability;

termites. Moreover, BYJU’S reports that since zinc chloride is also

•

ductility (can be drawn into wires – a single gram of

used as a ‘soldering flux’ (cleaning agent) which is capable of

gold can be drawn into a 2km-long wire, for example);

dissolving the oxide layer on the metal surface.

•

shine (known as metallic lustre).

Nichrome wire Take a look at your surroundings and think about what they are

Nichrome, which is silvery-grey in colour, is made up of a non-

made up of – metal or non-metal?

magnetic alloy of nickel, chromium and iron. According to TEMCo Industrial, nichrome wire is widely used in heating elements of

If you drop a utensil onto the floor, does it break? If not, chances

heat sealers, hair dryers, and ceramic support in kilns. It is found in

are it is metal as metals are generally hard in nature, although

various forms, ranging from nichrome 20 to nichrome 30 and 70.

the hardness varies from metal to metal. This is what’s referred

Nichrome 30, for example, is used for heating cables, floor heaters,

to as the malleability of metals. Since metal utensils are good

electric blankets and car seats.

conductors of heat, they are also commonly used for cooking.

Calcium hydride However, there are some metals that have properties that are not

Calcium hydride is considered an alkaline earth metal hydride. It

typical, such as mercury, which has a low melting point and exists

is a salt-like compound that is white and crystalline when pure.

as a liquid at room temperature.

However, it is usually found in grey-brown lumps and is used as a portable source of hydrogen, as well as a drying and reducing

According to ThoughtCo., the most abundant metal in the

agent and as a cleaner for blocked up oil wells, among other uses,

universe is iron, followed by magnesium. But here are a few other

explains the New Jersey Department of Health.

most popular metals, and what they are commonly used for in the real world:

Zinc phosphide

PALLADIUM Palladium metal is a rare and lustrous white material, as described by Bloomberg, and is one of the six platinum-group metals

Zinc phosphide, a metal phosphide, is a grey-black powder

(ruthenium, rhodium, osmium, iridium, and platinum itself). In

registered for use in pesticide products (also known as

October 2019, its price doubled in little more than a year, making

‘rodenticide’). It is made into bait that will attract the pest, such

it more expensive than gold.

as field mice and rats. The toxicity of zinc phosphide is due to phosphine gas exposure, explains the National Pesticide

It plays a critical role in pollution-control devices for cars and

Information Center, adding that it has an odour similar to that

trucks and is used aeroplanes. It is also used in dentistry as well

of garlic.

as jewellery, making it an incredibly versatile metal.

Science Stars Chemistry Issue | www.sciencestars.co.za

FOOD

THE SCIENCE OF FOOD CHEMISTRY TESTING DO YOU KNOW WHERE YOUR FOOD COMES FROM? WE TAKE A DEEPER LOOK AT THE PROCESS.

Created by KamranAydinov - www.free

By: Chireez Fredericks

Created by KamranAydinov - www.free

Science Stars Chemistry Issue | www.sciencestars.co.za

epik.com</a>

FOOD

n an age of healthy living and organic

nutritional label, therefore food needs

lifestyles, people are more concerned

to be analysed to verify these claims.

than ever about what they put into

Research and development are also

their bodies. With the help of food

necessary for manufacturers to improve

scientists and reliable food chemistry

their products and to provide high-

testing, we know exactly what is in the

quality food which is not only healthy but

food we are eating.

also affordable. In order to do this, it is important to study and analyse products

But what is food chemistry testing?

that are already in the market.

It is a process that food scientists use to verify the contents of the food we eat. It

By using special techniques to make sure

is a way to ensure consistent food quality

the foods we eat are safe, microbiology

and assist us in make healthier food

testing services aim to examine and

choices. Food chemistry testing can tell us

evaluate food products. The primary

how much sugar, protein, carbohydrates or

objective of the testing is to look for

fat are in a one serving of food. It can also

microbiological dangers that might be

inform us about whether or not there are

hazardous to humans such as e coli and

any food-borne germs and illnesses in our

salmonella, for example. Salmonella is

food products.

one of the leading pathogens that cause food-borne diseases, and scientific studies

With the changes in agricultural methods,

show that it is connected to raw fruits,

such as the use of fertilisers and

vegetables, juice, meat, eggs, poultry as

pesticides, as well as giving antibiotics to

well as many other foods.

animals to prevent diseases, food safety programmes have become increasingly

How do food scientists test food products?

important to securing food health.

There are many different techniques

This means that without testing food

that scientists can use for chemical

products, we cannot ensure whether or

food testing, such as traditional “wet

not the meals we are consuming are

chemical techniques” and more advanced

safe. Food safety is a crucial factor in the

techniques such as infrared spectroscopy

manufacturing and production of food,

and mass spectrometry. Mass spectrometry

and companies specialising in this rely

is the most frequently used type of

on chemical and microbiological testing

chemical testing that combines liquid and

laboratories to ensure the food they

gas chromatography in its analyses within

produce is fit for human consumption.

highly complex food matrices.

Food chemistry testing can be used to test

Within microbiological food testing,

organic food, to identify meat species, to

companies tend to use culture-based

analyse the nutritional value of our meals

techniques, like using selective agars

and can even assist us in making our

that aid in detecting pathogens in

food more appetising by showing us what

contaminated food and water. There is,

contributes to a more appealing taste,

however, an increase in the use of DNA-

texture and odour when it comes to food.

based and biomolecular techniques to analyse and test food safety. These

It can also help businesses minimise the

techniques identify potentially harmful

risk of food fraud by ensuring companies

microorganisms, food allergens and other

follow labelling regulations. All food

substances while identifying the source of

products must have a standardised

animal species of fish-based foods.

Science Stars Chemistry Issue | www.sciencestars.co.za

FOOD

Evidently, with the increase in food

interpreting the results, methods requiring

discovering ingredients to invent new

chemical testing, there have been amazing

gas and acid halo-identification can

recipes, concepts and you could even

advancements in chemical contaminant

provide ambiguous, hard-to-read results.

modify foods (fat-free foods, for instance).

analysis that now enable many food

This necessitates significant in-house

compounds to be analysed within a single

expertise to conduct, read and interpret

2. Product and process development

test run.

tests as there is no room for error.

scientist Do you want to understand and control

QuEChERS (pronounced as “catchers” and

What would happen if we didn’t have

the food development processes?

standing for Quick, Easy, Cheap, Effective,

regulated food testing in place?

Then this is just the job for you. In the

Rugged and Safe) is a sample preparation

Though it may be the last process of the

process development role, your main

method that evaluates the pesticide

food manufacturing chain, food product

aim is to optimise the performance of

residue in fruit and vegetables, as well as

testing is the most important step, because

manufacturing systems, by identifying and

antibiotics and compounds found in meat,

it determines the safety of the food that

developing new processes for product

fish and wine. As a chemical contaminant

is to be consumed. Food product testing

manufacture. As a scientist in product

testing technique that does not require

is necessary to ensure that the food is

development, you’ll work with research

any pre-concentration steps or excessive

free of physical, chemical and biological

scientists to develop new ideas and make

extract clean up, it has become the more

hazards. Examples of potentially hazardous

scientific discoveries.

preferred method of sample preparation

food contaminants include metals, e coli

used by chemical contaminant scientists.

bacteria, salmonella, cleaning agents,

3. Food product and ingredient

additives, preservatives and pesticides,

development scientist

among others.

Why not blend science and creativity with

In addition, gas chromatography and high-

the culinary art of food. In this role, you

resolution mass spectrometry instruments, as well as the development of related

Careers in the field

will develop tasty, healthy food that won’t break the bank of consumers.

software tools, have also seen their advancement and have displayed great

Do you want to play a role in bringing food

potential in food testing laboratories.

products from farm to fork? With a food

4. Research scientist

science degree, you can do just that! You

You’ll mostly be involved in planning,

What are the main challenges

will study the deterioration and process of

conducting experiments and analysing

encountered when testing?

food by using microbiology, engineering

results. This could either be for definite

Customary procedures of bacterial

and chemistry.

end use, such as to develop new products, processes or commercial applications,

indicator testing require preparation time and proficient lab skills. However, due

A food scientist determines the nutritional

or to broaden scientific understanding

to a lack of microbiological expertise

levels of food by analysing its content.

in general.

in food plants, samples are frequently

They look for new food sources, investigate

sent out to an offsite third-party lab for

the process of food manufacturing.

5. Scientific laboratory technician

culturing and results. This is often the

Food scientists also find the best way to

Your job is to provide all the required

more time-consuming and expensive

distribute, process, preserve and package

technical support to enable the laboratory

route as opposed to onsite testing which

the food.

to function effectively while adhering to correct procedures as well as health and

is cheaper. Some testing requires the use of a

Here are five careers your food science

safety guidelines. Your work will assist

degree to may lead to:

in the advancement and development of modern medicine and science.

spreader device, which can cause the test sample to spread outside of the

1. Food technologist

testing area, even when performed by an

The primary responsibility of a food

experienced technician. When this occurs,

technologist is to ensure that food

the test is considered invalid and requires

products are safe and meet specific

expensive and laborious retesting. When

standards. You could be involved in developing the manufacturing processes,

Science Stars Chemistry Issue | www.sciencestars.co.za

DIY

TRY YOUR HAND AT THESE DIY EXPERIMENTS WE TAKE A LOOK AT REVERSIBLE VERSUS IRREVERSIBLE PHYSICAL AND CHEMICAL CHANGES. By: Zakiyah Ebrahim

Sources: BBC Bitesize, Children's Encyclopedia Physics And Chemistry - MANASVI VOHRA

Science Stars Chemistry Issue | www.sciencestars.co.za

hat are reversible and irreversible changes? When two substances react and change and cannot revert to its original components, it is called an ‘irreversible change’. On the other hand, when two substances can be changed back to its original components after a change, it is known as a “reversible change”. Certain physical changes are reversible while others are not. On the other hand, most chemical changes are irreversible, as they occur at the molecular level and it is therefore practically impossible to reverse them. Instead, a new substance is formed through the chemical change and the original components lose their properties. The time it takes for chemical changes to happen can range from a few minutes (such as cooking) to many months, or even years (such as the rusting of iron, which we will explain later on). Many new substances are manufactured in factories and laboratories using different elements. Typical examples include nylon, plastic and steel – all of which are produced thanks to chemical reactions. These substances, in its new form, are better than their ingredients as they become useful in several ways.

DIY

In the case of physical change, this does not lead to the creation of a new substance or change the composition thereof. However, it may change the size, shape, or colour of a substance. Explaining these changes through simple examples: • Examples of reversible physical changes are bending plastic and then straightening it, or folding a piece of paper and then unfolding it. • Freezing water to make ice is an example of a reversible chemical change, explains the BBC Bitesize. • Physical change in humans, such as growing in height and losing our teeth is an example of irreversible physical change. • Baking a cake is an example of an irreversible chemical change, as it won’t allow you to reverse the ingredients into its original states. Practice reversible and irreversible changes with these DIY activities... 1. REVERSIBLE PHYSICAL CHANGE What you’ll need: • A glass of water • Sand Instructions: Take the glass of water and mix some sand in it. You will notice the water turn into a brown-tinted colour – this is because a physical change is taking place. If you leave it untouched for some time, the sand will start to settle at the bottom of the glass and the water will look clearer. Now, pick up the glass and carefully pour the water into another glass, ensuring the sand is left behind. This way, you have reversed a physical change since you now have both the ingredients – water and sand – back.

2. IRREVERSIBLE PHYSICAL CHANGE What you’ll need: • A bowl • Flour • Water Instructions: Mix the flour and water in the bowl. When you knead the dough, it is considered a physical change as the basic components of both ingredients (flour and water) remain the same. There is no chemical reaction, and therefore, no new component is formed during this process. However, you cannot reverse the change and get the flour and water back as the two separate ingredients that you started with. This is why it would be labelled an irreversible change.

3.IRREVERSIBLE CHEMICAL CHANGE What you’ll need: • A rusted piece of iron • Sandpaper Instructions: Rub the sandpaper against the rusted piece of iron. You will notice the rust coming off, but that the iron is not being restored to its original form. Once iron rusts, it weakens and consequently loses its properties. Rusting is one of the most common irreversible chemical changes that happen in our surroundings. This process occurs when iron is exposed to oxygen for a long period of time. Iron oxide (FeO) is formed by a chemical reaction, which is a red to brown colour. Science Stars Chemistry Issue | www.sciencestars.co.za

TOP PICKS

TOP 6 APPS SHARPEN YOUR SKILLS WITH THESE MOBILE APPS. By: Nicole Ludolph

Learning chemistry can be overwhelming. If you’re struggling with it, things like chemical formulas, structures and calculations sound like a foreign language. Luckily, there are dozens of apps that make learning chemistry easier. We have listed some of our favourites:

of questions that test your knowledge on chemistry, while still being easy to use. Some of the features included are an automatic pause-resume feature that allows you to go back to a quiz later, timed quizzes as well practice mode. Users can also pull detailed reports of their results.

Periodic Table | By the Royal Society of Chemistry

Virtual Chem Lab | By THIX

Learning the periodic table is fundamental to learning chemistry. While there are many periodic table apps available, the Royal Society of Chemistry app is special because of how interactive it is. Not only does it feature podcasts and videos, but it also allows users to customise the content displayed on the app. The slider feature illustrates how elements change as the temperature increases and users are able to learn additional facts related to the various elements.

This pocket-sized chemistry lab allows you to experiment with chemicals without any risk. Users can pour chemicals between beakers, mix them with glass rods or heat chemicals with Bunsen burners, just like in real life. There are 17 apparatus to choose from and hundreds of chemicals to play around with.

Learn Complete Chemistry | By Powerful Study House If you need an app that covers chemistry more comprehensively, this may be the one for you. This app includes a long list of topics including atoms and molecules, combustion and flame, and discovery of elements. Users can save notes around any of the subjects they would like to remember, as well as quizzes that allow users to evaluate their knowledge.

Chemistry Quiz! | By Sana Edutech One of the best ways to train your brain is by doing daily quizzes. The Chemistry Quiz! app is equipped with dozens

Chemical Equilibrium | By Wiki Kids Limited This app educates users around concepts such as reversible reactions, equilibrium states, and exothermic and endothermic reactions, among others. Chemical equilibrium is broken down into simple sections, underscored by a visually rich layout.

Chemistry Dictionary | By The Accidental Medico A particularly handy app, the Chemistry Dictionary provides easy to understand explanations of common and uncommon chemistry terms. The app is packed with definitions, synonyms and also teaches users how to pronounce words. With over 5 000 defined terms, users can bookmark definitions for future reference and access information both online and offline. Science Stars Chemistry Issue | www.sciencestars.co.za

STUDY TIPS

SEVEN STUDY TIPS STUDYING FOR YOUR CHEMISTRY EXAM DOES NOT HAVE TO BE A HEADACHE. HERE’S HOW TO MAKE IT EASIER FOR YOURSELF. By: Nicole Ludolph

Science Stars Chemistry Issue | www.sciencestars.co.za

STUDY TIPS

With enough time, patience and a proper study plan, you can ace even the most daunting chemistry tests. Here are helpful guidelines to make studying easier: Start with the basics Like with mathematics, a successful chemistry exam requires a fundamental understanding of a number of basic concepts. Concepts such as units, certain mathematical skills and how matter is classified, all form part of the core make-up of chemistry. Making sure that you understand these concepts will go a long way in overcoming any difficulties you may have with studying the subject. One way of ensuring understanding is compiling a list of key concepts along with their definitions. The list can be used to develop flash cards or other study aids. Refresh your maths Chemistry and mathematics overlap, therefore it only makes sense to brush up on the relevant mathematical concepts. As a budding chemistry ace, you should familiarise yourself with concepts such as scientific notation. Make sure you know how to convert between different units of measurement, as well as how to change the subject of a formula. Additional concepts that will prove useful are concepts such as rate, fractions and ratios, direct and indirect proportion, and the use of constants in equations.

day. Setting up a daily study schedule and sticking to it is beneficial for all your exams. Look after yourself Studying for hours on end without sleeping or eating well simply defeats the purpose. Going without sleep slows down even the smartest of people. To reach any type of academic success, you need to follow a balanced diet and get enough sleep and exercise. This is another reason why a balanced study schedule is important. Efficiency, efficiency, efficiency Increasing your study time is great, but studying without an efficient strategy could end up being a big waste of time. That is why it is important to make a study plan. You have already planned out how much time you are devoting to studying chemistry; the next step is figuring out how much time you need to devote to different study areas. Ask yourself where you need help the most, which concepts you know best, what you are already comfortable with, what you still find challenging. Allocate less time to those concepts you already know and need little help with. Focus more time on the areas you find most challenging.

Studying without an efficient strategy could end up being a big waste of time

Put it on repeat Another similarity chemistry has to maths is the obligation to practice often. Like physical exercise, chemistry becomes easier when constantly repeated. Try and obtain old exam papers, do the problems listed in your textbook (without looking at the answer first!) and complete chemistry exercises. Focusing on the areas you have difficulty with is also a good idea. Set aside enough time Practicing often requires a proper schedule. To ace your chemistry exam, you would need to study ahead of time. It should go without saying, but trying to cram the night before the exam will severely inhibit your chances of exam success. So, set some time aside every

Utilise all of your resources We live in an age where there is an incredible amount of information around, information that we can access for free. Broadcasters such as the SABC and eTV air television shows centred around high school revision, including the subject of chemistry. YouTube is an excellent resource for videos that break down and explain chemistry concepts. Chemistry apps for your smartphone are plentiful on Play Store and App Store, and setting up study groups with friends can be fun and educational. Chemistry need not be an overwhelming or hard to learn subject. The tools you need to learn it are close at hand. All you have to do is apply them effectively.

Science Stars Chemistry Issue | www.sciencestars.co.za

BURSARIES

FUNDING YOUR FUTURE Armscor What it covers: Tuition fees, prescribed books, accommodation, meals and vacation work when possible. Fields of study: • Aeronautical Engineering • Applied Mathematics • Biochemistry • Chemistry • Computer Science • Electronics Engineering • Electrical Engineering (Light current) • Ergonomics Science • Human Kinetics • Industrial Engineering • Information Technology • Marine Engineering • Material Sciences • Mechanical Engineering • Mechatronics Engineering • Metallurgy Engineering • Naval Engineering • Physics Who can apply? • South African citizens with a strong academic record • Those interested in working in the defence industry • Achieved a minimum of levels 5, 6, and 7 in Mathematics, Physical Science and English in Matric • Studying or intend on studying full time within one of the aforementioned fields of study at a recognised tertiary institute in South Africa • Those from a previously disadvantaged background How to apply: Applications must be submitted in one of the following ways: 1) Email: bursaries@armscor.co.za – use “Armscor Bursary Application” and your full name in the subject line. 2) Post: Senior Manager: Learning & Organisation Development Armscor LTD Private Bag X337 Pretoria 0001 Attach certified copies of the following documentation along with your completed application form: • ID document • Matric mid-year results, if currently in Matric • Matric certificate, if completed Matric • Full academic record, if currently at tertiary level • ID of parents/ guardians • Proof of income of parents/ guardians (latest payslips or

Science Stars Chemistry Issue | www.sciencestars.co.za

• • •

employment letter if employed/ affidavit if unemployed/ proof of SASSA grant if applicable/ death certificate if deceased) University registration/ acceptance letter (on letterhead) Fees statement, if currently at tertiary level (on letterhead) Covering letter (must state your field of study and what motivated you to choose to study in your field)

Closing date: 28 February 2021 Who to contact: Call 012 428 2421 or email Thembisp@armscor.co.za

Palabora Copper Bursaries What it covers: Tuition fees and residence fees, including a personal allowance of up to R5 000 for university candidates and of up to R4 000 for technikon candidates. Recipients will be required to sign a service agreement for a minimum time of two years. However, their service contract is one year for each year of study. Candidates may also be required to do vacation work at the company when necessary. Fields of study: • Mechanical Engineering • Chemical Engineering • Electrical Engineering • Mining Engineering • Metallurgical Engineering • Instrumentation Technician Who can apply? Candidates must: • Possess a valid South African ID • Be a South African resident • Bold a Grade 12 level of education • Have a strong background of Mathematics and have excelled in Physical Science • Show great discipline and a willingness to learn How to apply: Apply with your CV, cover letter and all required documentation. Visit palabora.com/training_and_development.asp for the application process. Closing date: Before the end of August. Who to contact: Email either bursary.applications@palabora.co.za or Learnership.Bursary@palabora.co.za

QUIZ

PICKING YOUR BRAIN

1 2 3 4

Chemistry is about… A. Numbers and mathematical sums only B. Matter and how it changes, as well as the production and use of energy C. Building apartments and houses

Which of these is not a physical property of a metal? A. Liquidity B. Malleability C. High melting points

What happens to water when it freezes? A. It expands B. It explodes C. It forms tiny crystals

Which of the following is applied to wooded furniture to prevent termites… A. Zinc chloride B. Zinc phosphide C. Calcium hydride

What is the chemical name for water? A. NH3 B. H2O C. CO2 Which is the only letter that doesn’t appear on the periodic table? A. X B. Z C. J

Most chemical changes are… A. Dangerous B. Irreversible C. Reversible

What is one the most common irreversible chemical changes? A. Forming of ice B. Rusting C. Melting of ice

Which career in food falls under the chemistry industry? A. Cattle farming B. Food technologist C. Chef

What’s an easy way of having the periodic table readily available at all times? A. Write it down on your arm B. Keep a paper in your pocket C. Download a mobile app on your phone

Science Stars Chemistry Issue | www.sciencestars.co.za

PUZZLES

SUDOKU Fill in the 9×9 grid with digits so that each column, row, and 3×3 section contain the numbers between 1 to 9. 51 38

26 41

13 9

3 6 6

1 42

31 5 9

42 8 1

6 7

94 4

2 39

15 6

36 55

WORD SEARCH El

U U

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CW S

N C

A R

M D

CGT

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A N

YO K

CCG

SA G

M M

A H

SEG

APY

N U

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RHE

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B I

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H W

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ATR

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N I

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S Y

G S

S E

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SDS

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R E Liquid T Biochemistry S D Bunsen U G K Laboratory U C E Flammable N E S Hydrogen C Metal I D A Elements E S Reaction I D N Energy A D E

G S

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TVE

Science Stars Chemistry Issue | www.sciencestars.co.za

ANSWERS

TEST RESULTS What was your score for the Women In Science issue?

SUDOKU 2 4 23

86 1 5

86 9 7

57 38 9

4 8 6

53 2

7 81

74 9 3

21 2 5

95 6 8

23 1

9 3

6 87

4 24 1

76 3 92 59

41 7

56 5 61 79

13 4

79 7

13 6

4 3

5 1 2 6

85 6

35 26 8

16 72 9

9 35 57

41 4 3

68 4

QUIZ

WORD SEARCH

1. A - Keimoes 2. B - Horticulturist CE

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A E W 3.T C - Dorothy Jackson

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you’ve recovered R

G pathology K A 7.UB - Plant

8.UB - Stellenbosch C E

5. C - 390 000 T

6. A - Turmeric

9. B - Plant life N

I N

10. C - Toothache

Science Stars Chemistry Issue | www.sciencestars.co.za

FACTS

BET YOU DIDN’T KNOW THAT… 1

Water expands when it freezes, so an ice cube takes up about 9% more volume once it’s frozen.

Oxygen, in its gas form, is colourless but is blue when found in its liquid or solid form.

If you take a glass that’s filled with water and add a handful of salt to it, the water level will go down instead of overflow. This is in direct contract to Archimedes’ Law, which would see the water level rise once you step into a bathtub, for instance.

Water is essential to our survival, but too much of it could cause death. Also, by the time your body notifies your brain that it’s thirsty, you’ve already lost roughly 1% of your available water.

H2O (or dihydrogen monoxide) is the chemical name for water.

Helium is lighter than air, which is why helium balloons float.

“J” is the only letter of the alphabet that doesn’t appear on the periodic table.

Dry ice is actually carbon dioxide (CO2) in its solid form.

Gold and copper are the only non-silver metals.

Science Stars Chemistry Issue | www.sciencestars.co.za

Glass consists of flowing molecules that move so slowly that the movement can’t actually be seen. Glass is therefore called a amorphous solid, which lies between a solid and a liquid form.

SCIENCE CENTRE

CENTRE OF ATTENTION:

OSIZWENI SCIENCE CENTRE Packed with fun, science and technology lovers can enjoy a visit to one of Mpumalanga's most enticing centres.

ith a motto like “Bringing Science alive: touch it, feel it, live it… inspiring tomorrow’s scientists”, you’re guaranteed to have a blast of delight while absorbing information at one of South

Africa’s leading science centres. Situated in the outskirts of Secunda, Osizweni Science Centre (OSC) provides teachers and learners in historically disadvantaged communities across Mpumalanga’s Gert Sibande district with structured support in Science, Technology, Engineering and Mathematics (STEM) education. The centre is a Sasol initiative and was founded in 1991, and has grown from a skills development centre to an impressive leading provincial education hub. What does it offer? OSC offers development programmes for teachers and educational resources and programmes for Grade 8 to 12 learners. As a focused hub of STEM education expertise, their aim is to address the imbalances in Mathematics and Science education and to improve the matric pass rate, thereby helping to bring about new generations of leaders for the industry. To achieve this, OSC focuses on two programmes: early childhood development (which includes a toy library) and STEM education support, with some interventions starting at primary school level. Current support provided to the Mpumalanga Department of Basic Education in the Gert Sibande region includes:

•

Enhancing learner performance in Mathematics,

Science, Accounting and Life Science.

Teacher training and development in Mathematics,

•

Science Stars Chemistry Issue | www.sciencestars.co.za

SCIENCE CENTRE

Science and Accounting.

•

Ensuring that OSC’s School Management Teams are

mentored and developed in their leadership and

management skills. The interactive teacher workshops are held to enhance teacher skills and knowledge of subject content, and are run in partnership with the Department of Basic Education (Gert Sibande District) and KPMG. Interactive exhibits OSC also hosts exhibitions in order to bring the exciting STEM to life for both students and teachers, as well as the general public at large. Activities that you can expect include mobile Science and Technology exhibits, Science shows and motivational talks. Mobile Lab Programme It is also one of the first science centres in the country to implement a well-equipped Mobile Lab Programme, with state-of-the art science apparatus giving learners the opportunity to gain exposure to curriculum-based, hands-on experiments. Career guidance Career guidance is offered in order to stimulate an interest in STEM careers. Described as a customised “one-stop” service, OSC’s fully-fledged Career Guidance Centre’s goal is to help put learners on the road to self-discovery. If you’re interested in this service, you can expect the following: a basic individual assessment, career information and planning, and help with bursary applications and university admissions.

Who can visit? Although the centre provides direct educational support to 27 secondary schools in the Standerton sub-region of the Gert Sibande district, it is also open to nationwide visitors. You can find the centre at: Old Bracken mine, Bracken Road, outskirts of Secunda, 2302. Call them on 017 689 2006/8, or visit their website at osizweni.org.za.

Science Stars Chemistry Issue | www.sciencestars.co.za

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Scientists, Technologists and Innovators are just like you. They’re curious. They ask questions. They try new things. The desire to try new things has been inside you from the very beginning.

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