Students must be made to wear safety goggles, lab coat, and shoes in the

Your pulse measures how many times your heart beats in one minute. Your pulse goes up when you exercise.

Record your pulse when you are resting, and fill in the table. Now jog on the spot or do star jumps for two minutes. Measure your pulse again and fill in the table.

Resing Pulse (beats per minute) Pulse After Exercise (beats per minute)

What is the effect of exercise on your pulse rate? Use your table to help you decide.

TASK FOUR: Adaptations

Plants are different from one another because each one is adapted to the environment it grows in.

Join up the boxes with the name of the plants, where they grow and how they are adapted to living in those conditions. The pictures will give you a clue.

Seaweed

Foxglove

Marram Grass

live in shady areas

lives in salty water and on rocky seashores

lives in fresh water water is stored in the fleshy parts of the plant, and leaves are covered with wax so they don’t lose too much water. has large leaves that float on the surface of the water to collect the sunlight, and long leaf stems that go down into the water

has very long roots that can reach down to the water

Water Lily

Cactus

lives in desert areas

lives in sandy areas likes damp conditions but has long flowers that reach up to the sunlight

has gas filled bubbles to help it float on the surface of the water

WEEK 4: CHEMISTRY

TASK ONE: Acids and alkalis

Indicators and pH

Litmus paper tells us whether something is an acid or an alkali. But it does not tell us the strength of an acid or alkali.

A universal indicator can tell us whether we have strong acid or a strong alkali by producing a pH scale.

Red means a strong acid, blue means a strong alkali. Green means a neutral solution.

How acidic? How alkaline?

We can’t use litmus paper to find out the strength of vinegar compared to stomach acid or lemon juice. As the paper would turn red, regardless of strength.

Instead, you need a universal indicator. Universal indicator is a mixture of dyes, it changes colour to show how acidic or alkaline the solution is.

The pH scale is a measure of the strength of an acidic or alkaline solution.

• An acid will always have a pH lower than 7, the closer to 1 the pH is the stronger the acid is. • An alkali has a pH of more than 7, the higher the pH the more alkaline the solution is. • Some solutions are neutral, this means neither acidic or alkaline - this pH of a neutral solution is exactly 7.

Draw lines from the following substances to the correct category:

Lemon Soap ACID Vinegar Coca cola ALKALI Toothpaste

Litmus paper is an indicator paper, what colour would:

Red litmus paper turn in acidic solution: _______________________________________ Red litmus paper turn in an alkaline solution:___________________________________ Blue litmus paper turn in an acidic solution:____________________________________ Red litmus paper turn in an alkaline solution:___________________________________