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SCIENCE YEAR 10 SUM MER BO O KL ET Happy Summer, Year 10! This resource is a booster pack to help you review everything that you should have learnt in Year 9 and help you when you begin Year 11 – leading up to your GCSEs. There are a variety of activities, and the answers are available for you to check so you know if your understanding is strong or has areas that need a little extra work. Although the last few months have been difficult, and you might well be feeling anxious about Year 11, we have built time into your Year 11 Science lessons to re-visit the learning so far, especially the content you met and learnt for the first time during ‘lockdown’. Saying that, if you’ve had a good go at the tasks in this pack, and gone back to check on things you found more difficult first time through, you’ll be in a strong position for starting the coming year. There are links to GCSE pod videos to help you with your understanding, if you come across something you don’t understand, and below are some links to other places you can find help. The topic headings will also help you as there will be revision resources on SharePoint for you to access to help with each topic.
Enjoy Science Team at Delta
Science
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ECOLOGY
WEEK 1 ADAPTATIONS
DEMONSTRATE TASK
Adaptations are ways that a species is well-matched to the surroundings and environment. These are often visible features.
The picture shows a basilisk lizard. Some of the adaptations of the lizard are labelled.
1. 2.
Describe the differences between the fennec fox (left) and the arctic fox (right).
Long tail
Brown skin
Basilisk lizards are often found resting on branches of trees that grow next to water. Basilisk lizards can run across the surface of the water.
Try and explain the differences described.
Give a reason for the following:
a.
b.
c.
Webbed toes
Toes on feet are webbed Long tail Brown skin
SURFACE AREA TO VOLUME
(3 marks)
CHALLENGE: The size of an animal is important for its survival. You usually find bigger organisms living in colder climates where they need to keep as much heat as possible. The smaller surface area in relation to volume allows them to do this effectively. For each of the ‘organisms’ below work out the surface area, volume and then surface area to volume ratio. B.
A.
Suggest one advantage to the basilisk lizard of being able to run across the surface of the water
DISTRIBUTION OF ORGANISMS
C. Ecologists study the make up of biological communities and ecosystems. They look at how biotic and abiotic factors can affect the abundance and distribution of organisms. To do this they need to use a special piece of apparatus called a quadrat. A quadrat is a square empty metal frame usually 50cm x 50cm. 4
They can be used in 2 different ways:
2 1
2
2
SA
SA
SA
Vol
Vol
Vol
SA:Vol
SA:Vol
SA:Vol
Large surface area:volume
Animals retain more heat
Small surface area:volume
Animals can lose and gain heat much faster
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2.
Investigate distribution along a transect.
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Calculate the total area of these quadrats in metres:
1m
2
Estimate population size in a large area.
50cm
1
1.
25cm
1
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WEEK 2 - FORCES AND ENERGY
WEEK 1 CARBON CYCLE
VECTORS AND SCALARS
This diagram shows how carbon is circulated into the atmosphere and out of the atmosphere as well as being passed from one organism to another.
Quantities we measure can be either a vector or a scalar. Scalars are just a size of magnitude, like temperature or energy, money. Vectors are also size of magnitude but they also need a direction for them to be meaningful, like a force of 10 Newtons isn’t much use unless you know if it was upwards or downwards or to the left etc. Here is a list of quantities. See if you can match them up into the correct category.
Scalars
Vectors Displacement
Displacement, temperature, speed, mass, weight, *velocity, energy, distance, resistance, force, charge, surface-pressure *velocity is speed in a chosen direction
e.g displacement is distance travelled in a certain direction from its original position, so it’s a vector
COMBINATIONS OF VECTORS When vectors add together, we need to take the direction into account. A 3N force and a 4N force acting in the same direction will add together to give a 7N force to the right, but if the 3N force was to the left, the result would only be 1N to the right because 4N – 3N is 1N. Example: What is the overall force (often called the ‘resultant force’) acting here? Answer: Resultant Force: 4N and 3N left = 7N, 5N and 6N right = 11N, 11N – 7N = 4N to the right.
3N 4N
3N 4N 5N 6N
Lower-Demand 1.
Which organisms take carbon dioxide from the air?
2.
When animals eat plants they use the glucose for which process? What gas does this release into
the air?
3.
What is decay?
1.
4.
What three things do all living organisms make out of carbon atoms?
a. What is the resultant force in a tug of war competition when one team pulls right with 240N and the other team pulls with 320N in the opposite direction?
Higher-Demand
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1.
Describe how carbon is removed from the air.
2.
What process do all living organisms do that returns carbon back to the air?
3.
Why are microorganisms included in the carbon cycle?
4.
Why do plants need carbon? What do they use it to make? (Think back to the last biology unit where
we learnt about the uses of glucose)
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QUESTIONS Draw diagrams to show these forces and show the resultant.
b.
Draw a scale vector diagram showing the resultant force of 3N and 5N pushing a mass west.
c.
Draw a scale vector diagram showing the resultant force of 4N and 2N pulling a mass west.
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FORCES AND ENERGY
WEEK 2 HIGHER ONLY
WEIGHT AND MASS
When the vectors are not in the same direction, it’s a little harder. You can draw a scale-diagram of the forces, using an easy scale like 1cm = 100N, making sure you draw the arrows tip-to-tail (3b). The red arrow – from the
Mass is the amount of material an object is made up of, and is measured in ‘kg’. Weight is the force that gravity causes on that mass, and is measured in ‘Newtons’.
start of the first force to the end of the last force – shows the resultant. If you measure that, it will give you the
Weight = mass x gravity strength
force, drawn to the same scale.
On Earth, gravity strength is almost 10 Newtons per kilogram (10N/kg). The actual figure is 9.8N/kg but a question might well just let you use 10.
You can then use a protractor to
QUESTIONS
measure the angle that force is at. E.g if arrow A represents 400N and
B = 300 N
R = 500 N
is 4cm long, and arrow B represents 300N and is 3cm long, then drawn correctly arrow R would be 5cm long and represent 500N. The red
θ
A = 400 N
1. B = 300 N
a) 2kg 2.
A = 400 N
What would the weight of these masses be on Earth, assuming g = 10N/kg? b) 20kg
c) 200g
c) 2kN
What is the mass of an object that on Earth weighs
a) 100N
b) 1.5N
3.
The gravity on the Moon is 1.6 N/kg. Explain why astronauts can wear spacesuits on the Moon that
arrow R is 37° above horizontal.
would crush them on Earth.
2.
For each of the following, draw a diagram and work out the resultant vector.
a.
James sails 1000km west in his boat and then turns North and travels for a further 750km.
b.
Phil bikes 40m then turns left and travels for 25m.
Figure 3(a)
Figure 3(b)
WORK DONE Work Done is the energy (in Joules) transferred moving an object. Work Done = Force x Distance (in the direction of the force) The work done here is just the weight x height lifted. The force and distance are in the same direction.
3.
Explain why 5N + 4N does not always mean a resultant force of 9N.
Make sure the force is in NEWTONS and the distance in METRES.
FORCE AND EXTENSION – HOOKE’S LAW
TRIPLE ONLY
One of the required practical activities involves investigating Hooke’s Law, which describes how elastic objects stretch when a force is applied.
If the forces are not at 90° as in fig.2, draw scale arrows, using a protractor to get the correct angle to horizontal, then once again measure the red resultant.
Explain how you would use the apparatus shown to investigate how the extension of a spring is affected by the load force hanging from it. Include safety precautions.
214 N 150 N
100 N
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Figure 2
[2]
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FORCES AND MOTION
WEEK 3 DISPLACEMENT-TIME GRAPHS
VELOCITY-TIME GRAPHS
NEWTON’S LAWS OF MOTION
Displacement is how far an object is from its original
Velocity is speed in a fixed direction. Velocity-time
NEWTON’S 1ST LAW
position, so a displacement-time graph shows how
graphs show how the velocity of an object varies
this changes as time passes during a journey (or
during the time of a journey.
Newton’s 1st Law means UNBALANCED FORCES cause ACCELERATION (note - this is not a statement of Newton’s 1st Law, this is just how it works.) If the object is originally AT REST (stopped) it will SPEED UP FORWARDS or BACKWARDS. If the object is already moving with a CONSTANT VELOCITY it will SPEED UP in the direction it’s moving or SLOW DOWN. (It might even start to go backwards if
whilst the object is stopped).
Velocity can be a negative value if an object is
Using the graph we can work out the speed of an
travelling in the opposite direction to the one
object by looking at the steepness of the line and
chosen, for example if you choose ‘upwards’ as
finding the gradient (how far up divided by how
the positive direction then ‘downwards velocities’
far along that section goes).
would be negative.
the force acts for long enough!)
Like with displacement graphs, the gradient of
1.
1.
There is a more suitable physics word for
the line can tell us something – in this case the
‘getting faster’. What is it?
acceleration.
State Newton’s 1st law of Motion.
Acceleration = change in velocity/time
NEWTON’S 2ND LAW
HIGHER ONLY On higher exams you might be asked to determine the distance an object has travelled on the journey, which is the area under the graph up to that point. The area can be split into rectangles and triangles,
Newton’s 2nd Law is the equation F = m x a, which tells us how much force is needed to make a mass accelerate at a certain rate. F = m x a a = F/m m = F/a 1N of force on 1kg of mass causes 1m/s² of acceleration. 2.
Calculate the acceleration on this block if all the forces are shown.
and the usual maths rules used to calculate them. You might also, as with displacement graphs, be asked to find an acceleration at a certain point on a curve using the gradient of a tangent.
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NEWTON’S 3RD LAW Newton’s 3rd Law is that every force or action has an equal, opposite reaction force. What this means is that when one object causes a force on another object, an equal force acts back on the first object.
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WEEK 4
WEEK 3 THINKING, BRAKING AND STOPPING
HOMEOSTASIS AND THE NERVOUS SYSTEM
STOPPING is made up of two stages – THINKING then BRAKING.
1. What is homeostasis? 2. Name 3 things we have to keep balanced. 3. What do glands in the endocrine system do? 4. What are the main differences between nervous and endocrine signals in the body? 5. Which gland in the body detects changes in glucose concentration in the blood? 6. Why would blood glucose levels increase? 7. Why would blood glucose levels ever decrease? 8. What is glycogen? 9. What is type 1 diabetes? 10. What are the treatment options for type 1 diabetes? 11. What is type 2 diabetes? 12. What are the treatment options for type 2 diabetes?
You should know the factors that affect each process. 1. State three factors that affect a motorist’s thinking distance/reaction time. CAREFUL! “Increasing your reaction time” means you react SLOWER. 2. State three factors that affect a motorist’s braking distance/friction provided.
13. How long does the menstrual cycle last? 14. When does ovulation occur? 15. When does menstruation occur? 16. What happens to the uterus wall between days 6-28? Hormone
What does it do?
FSH
Oestrogen
LH
Progesterone
17. Why do contraceptive pills mainly contain progesterone? 18. What are the advantages of using barrier methods over hormonal methods of contraception? 19. Why are some people more opposed to the use of IUDs than other forms of contraception?
HIGHER ONLY 20. What are fertility drugs and why are they given? 21. What are the main stages in IVF treatment? 2. 3. 1. 22. What are the downsides of IVF treatment?
4.
5.
.
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WEEK 4
HOMEOSTASIS AND THE NERVOUS SYSTEM
EXAM-STYLE QUESTIONS
THE NERVOUS SYSTEM
Q1. A person with Type 1 diabetes does not produce enough of the hormone insulin. (a) Where is the hormone insulin produced?
1. What is a stimulus? 2. What are receptors?
Tick one box.
3. Where are receptors found? • Light
• Taste
• Smell
Brain
Pancreas
4. What is the central nervous system made up of?
• Pain
• Touch
• Temperature
5. What are effectors?
Pituitary [1]
Thyroid
6. What are the 3 main types of neurones?
8. Why are they faster than normal nervous responses?
[1]
(c) People with diabetes may be asked to control their diet. Explain how this can help to reduce the risk of developing health problems.
9. What are the main 6 stages?
10. Describe what happens when the thumb
an [3] [Total 5 marks]
impulse along the
impulse passes a
neurone. It then passes another synapse into
(a) What type of chemical is thyroxin?
and sends
neurone to the
Q2. Thyroxine is produced by the thyroid gland and released into the blood.
detects the
a
HIGHER ONLY
Reflex Arc
touches something sharp.
The
7. What are reflexes?
(b) How does insulin travel around the body.
. The into the
neurone. This sends an impulse to the
example causes the
which in this to contract
their arm away from the pain.
11. What is a synapse? [1]
(b) People in stressful situations produce a chemical that reduces the activity of the pituitary gland. Explain how this can cause people to gain weight.
12. How do electrical impulses pass across? 13. How can we do an experiment to see how
caffeine affects our reaction time?
14. What would you expect to happen?
12
• Sound
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[3] [Total 4 marks]
Chemical Synapse
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WEEK 5
WEEK 4 TRIPLE ONLY
GET AHEAD: INHERITANCE
15. How can we find out more about how the
Sexual reproduction involves the joining of male and female gametes. A gamete is the scientific term for a sex cell. In animals, the gametes are the sperm and the egg cells. In flowering plants, the gametes are the pollen and the egg cells. In sexual reproduction, mixing of genetic information occurs which leads to variety in the offspring.
brain works?
16. Match up the part of the eye with its function. Pupil
The white outer layer of the eye. It is tough and strong but has a transparent area at the front.
Lens
Coloured muscle that opens and closes the pupil to allow different amounts of light into the eye to protect the retina.
Iris
Contracts and relaxes to change the shape of the lens.
Retina
The opening made by the iris to allow light to enter the eye.
Cornea
A sheet of light-sensitive receptors called rods and cones.
Sclera
Carries electrical impulses from the retina to the brain.
Ciliary Muscle
These attache the ciliary muscles to the lens.
Suspensory Ligament
A clear disc that fine tunes the focusing of the light rays to produce a clear image on the retina.
Optic Nerve
Transparent area at the front of the sclera that lets light into the eye. It changes the direction of light to focus it on to the lens.
17. What is accommodation? 18. How we see close objects? 19. How do we see objects that are further away? 20. What is myopia?
Every new offspring formed is unique. The gametes are produced by meiosis. Asexual reproduction involves only one parent. There is no fusion of gametes. No mixing of genetic information occurs. All offspring are genetically identical (called clones). Only mitosis is involved. Meiosis leads to non identical cells being formed. Mitosis leads to identical cells (clones) being formed. Cells in the reproductive organs divide by meiosis to form gametes. In animals, the reproductive organs are the ovaries and testes. Meiosis is sometimes called reduction division because it halves the number of chromosomes in the gametes. When male and female gametes fuse during fertilisation, the number of chromosomes are restored. This brother and sister have the same parents, but they look different. They show variation because of meiosis. A cell in the testes has 46 chromosomes. When this cell undergoes meiosis it produces 4 gametes each with 23 chromosomes. The same process occurs in the ovary to produce egg cells. The male and female gametes join at fertilisation to restore the normal number of chromosomes. The fertilised egg cell now contains 46 chromosomes. a. b. c.
Fertilisation occurs. The genetic material from the sperm and egg combine to form a unique cell. The fertilised cell divides by mitosis to form 2 identical cells. Both cells divide by mitosis to form 4 identical cells.
There are advantages to both sexual and asexual reproduction. Advantages of sexual reproduction
Advantages of asexual reproduction
Variation occurs in the offspring
Only one parent is required so it is a more efficient use of time and energy as do not need to find a mate
If the environment changes, variation will give a survival advantage by natural selection. There is a better chance of at least some organisms surviving,
Many identical offspring can be produced if conditions are favourable.
Natural selection can be manipulated and sped up by humans, by selective breeding to increase food production.
Occurs faster than sexual reproduction
21. How is it corrected? 22. What is hyperopia? 23. How is it corrected?
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GET AHEAD: INHERITANCE
WEEK 5 TRILOGY AND TRIPLE
TRIPLE ONLY - CONT.
The genetic material in the nucleus of most cells is made from a chemical called DNA. DNA is a polymer made from two strands which twist around each other making a spiral ladder.
Proteins have many different vital functions in our body. • Enzymes – all made from protein. • Hormones – all made from protein • Antibodies – all made from protein • Structural components such as muscle, hair and nail tissue.
DNA stands for deoxyribonucleic acid. You don’t need to remember this! DNA is arranged in structures called chromosomes inside a cell’s nucleus. A gene is a small section on a chromosome. Each gene codes for a particular sequence of amino acids, to make a specific protein. A human has approximately 24,000 genes in total. Each single chromosome is made up of about 2000 genes. In human body cells the chromosomes are normally found in pairs. Each cell has 23 pairs of chromosomes. The chromosome number varies from one organism to another. A horse has 32 pairs of chromosomes and a housefly has 12 pairs. The Human Genome Project (HGP) was an international scientific research project set up to map all the genetic information in a human being. It began in 1990 and was completed in 2003. The whole human genome has now been studied and this will have great significance for medicine in the future. This work to understand the human genome is important for several reasons: • To enable scientists to search for the genes linked to different types of disease to look for possible treatment or correction • To enable doctors to better understand and treat inherited disorders • To be able to trace historic human migration patterns
TRIPLE ONLY
It is estimated there are over 2 million proteins in a human body and all are made from combinations of just 20 different amino acids. A sequence of three bases is the code for a particular amino acid. The order of the bases controls the order in which amino acids are assembled to produce an individual protein. When the protein chain is complete, it folds up to form a unique shape. This unique shape allows the protein to carry out its role effectively. This could be as an enzyme, hormone or structures in the body such as collagen.
CHECK YOU’RE UNDERSTANDING
Malarial parasites
Reproduce asexually in the human host, but sexually inside a mosquito.
Fungi
Reproduce asexually by spores, and sexually to give variation.
When daffodils flower they produce seeds. This is sexual reproduction. Daffodils also reproduce asexually by bulb division. Strawberry plants produce seeds sexually and reproduce asexually using runners. A genetically identical plant forms at the end of the runner. DNA is made from repeating monomers called nucleotides. There are 4 different nucleotides. The long strands of DNA consist of alternating sugar and phosphate sections. Each nucleotide is made from three components: • A phosphate group • A simple pentose sugar (this means it contains 5 carbon atoms) • A base There are 4 bases in DNA. • Adenine (A), thymine (T), guanine (G) and cytosine (C) Notice in the diagram that adenine always pairs up with thymine or vice versa. Cytosine always pairs up with guanine or vice versa. This is called complementary pairing.
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Genes provide the instructions to make the required protein from amino acids.
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1. 2. 3.
What is a gamete? Name the male and female gametes in a. a human b. a daisy plant b. a. For each row, tick one box to show which method of cell division is correct Meiosis
Mitosis
Genetic mixing happens Gamete production occurs New cells show variation New cells have same number of chromosomes as parent Happens in skin cells Two divisions occur Two new cells are formed as a result Identical cells are formed
4. How many chromosomes are found in the nucleus of a human b. egg cell? a. ovary cell? c. embryo cell? d. a cell just after fertilisation has occurred e. testes cell? 5. Name the shape which best describes the DNA polymer 6. How is DNA organised inside the cell nucleus? 7. Which is larger, a chromosome or a gene? 8. What does a gene code for? 9. Write down the definition of the genome of a horse 10. List two reasons why it is important to understand more about the human genome
Triple only 11. What are three advantages of sexual reproduction? 12. What are three advantages of asexual reproduction? 13. List three organisms which reproduce using both sexual and asexual reproduction methods. 14. Where would you find a nucleotide? 15. What does a nucleotide consist of? 16. What are the symbols of the 4 bases found in DNA? 17. What does the code for an amino acid consist of? 18. Fill in the missing terms: and The long strands of DNA are made of alternating sections. Attached to each is one of the four units. bases. The DNA polymer is made up of repeating
Higher Tier biology only 19. In the complementary strands of DNA – which base is T always linked to? 20. Which organelle in the cytoplasm carries out protein synthesis? 21. What do carrier molecules bring to the organelle from the cytoplasm? 22. What happens in protein synthesis once the protein chain is complete?
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GET AHEAD: RATES OF REACTION
WEEK 6 GET AHEAD: RATES OF REACTION
FACTORS AFFECTING RATES OF REACTION
The rate of a chemical reaction can be found by measuring the quantity of a reactant used or the quantity of product formed over time.
Factors which affect the rates of chemical reactions include: • The concentrations of reactants in solution • The pressure of reacting gases • The surface area of solid reactants • The temperature • The presence of a catalyst
quantity of reactant used time taken
Mean rate of reaction =
Mean rate of reaction =
quantity of product formed time taken
The quantity of reactant or product can be measured by the mass in grams or by a volume in cm3. The units of rate of reaction may be given as g/s or cm3/s Worked example 1 25cm3 of carbon dioxide was given off in the first 2 seconds of a reaction. Calculate the mean rate of reaction and give the units.
Mean rate of reaction = 25cm3 / 2 s
Collision theory explains how these factors affect rates of reactions. According to this theory, chemical reactions can occur only when reacting particles collide with each other and with sufficient energy. The minimum amount of energy that particles must have to react is called the activation energy. Increasing the surface area, temperature or using a catalyst will increase the rate of reaction so the gradient of the line increases from B to A.
Mean rate of reaction = 12.5 cm3/s
The difference is that increasing the concentration provides more reacting particles therefore more product.
Mean rate of reaction =
quantity of product formed time taken
Worked example 2 (Higher Tier) The above reaction was carried out again. The new results showed that 2 dm3 of carbon dioxide was released in 200 seconds. Calculate the mean rate of reaction in mol/dm3. (1 mole of any gas occupies 24 dm3 at STP) 2 dm3 = 24 dm3 0.83 moles = 200
Moles of carbon dioxide =
0.83 moles
Mean rate of reaction =
0.0042 mol/s
CHECK YOU’RE UNDERSTANDING 1. State two ways of finding the rate of reaction 2. State two units of rate of reaction. (HT: state 3) 3. State two ways of measuring the quantity of reactant or product 4. A student carries out an experiment reacting hydrochloric acid (HCl) with calcium carbonate (CaCO3) to give calcium chloride (CaCl2) carbon dioxide and water. Write the balanced symbol equation for this reaction. 5. The student collects 50 cm3 of carbon dioxide gas in 10 seconds. What is the rate of reaction? Include the units. 6. (HT only) The student repeats the experiment again, this time they find the mass of the carbon dioxide collected. They collect 11 g of carbon dioxide in 10 seconds. Calculate the rate of reaction in mol/s. 7. (HT only) What mass of carbon dioxide are they collecting per second if the rate of reaction is 0.075 mol/s?
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FOUR FACTORS Concentration: Increasing the concentration of reactants in solution increases the frequency of collisions, and so increases the rate of reaction. Pressure of Gas: Increasing the pressure of reacting gases increases the frequency of collisions, and so increases the rate of reaction. Surface Area: Increasing the surface area of solid reactants increases the frequency of collisions, and so increases the rate of reaction. Temperature: Increasing the temperature increases the frequency of collisions and makes the collisions more energetic, and so increases the rate of reaction.
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WEEK 6
NOTES
CATALYSTS Catalysts change the rate of chemical reactions but are not used up during the reaction. This means that the catalyst is still there, unchanged, at the end of the reaction. Different reactions need different catalysts. Enzymes act as catalysts in biological systems. Carbohydrase is an enzyme/catalyst that only breaks down carbohydrate. Chlorophyll is the catalyst that enables carbon dioxide and water to react together to make glucose during photosynthesis. Catalysts increase the rate of reaction by providing a different pathway for the reaction that has a lower activation energy. A reaction profile for a catalysed reaction can be drawn as shown here. The graphs show how the energy changes in a reaction are different with an enzyme, but the graph is the same shape for any type of catalyst, not just a biological catalyst. You should be able to explain catalytic action in terms of activation energy. For example, “from the reaction profile I can see that the catalyst lowers the activation energy”.
CHECK YOU’RE UNDERSTANDING
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1. What is meant by the term ‘collision theory’? 2. What is meant by the term ‘activation energy’? 3. What happens to the gradient of a line if the rate of reaction is increased? 4. What is a catalyst? 5. According to collision theory, chemical reactions can only occur when... 6. Other than concentration give three factors that affect the rate of reaction.
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7. Draw a labelled graph to show how changing any one of these factors may affect the rate of reaction. Include the line before and after the change.
8. What is a catalyst? 9. The symbol equation for photosynthesis is: 6CO2 + 6H2O C6H12O6 + 6O2 The catalyst for this reaction is chlorophyll, however it does not appear in the equation. Why is this?
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NOTES
ANSWERS Use your camera to unlock the answers with this visual key.
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