1. In the red 1 Name three indicators.
7Ec
In the red
1 Name three indicators.
2 What colour would purple litmus go if you mixed it with:
a) sulphuric acid
b) tap water
c) lemon juice?

2. 7Ec
In the red
3 A few drops of litmus solution were added to some toothpaste. The litmus turned blue. What does this tell us about toothpaste?

3. 7Ec
In the red
4 Sally crushed up some purple berries from a bush, and mixed them with a little water. When she mixed the juice with some washing powder, it changed colour to red.
a) Is the berry juice acting as an indicator? Explain your answer.
b) Which of these best describes the washing powder? A-definitely an acid; B-definitely not an acid; C-possibly an acid. Explain your answer.

4. In the red 1 Name three indicators.
7Eb
In the red
1 Name three indicators.
For example: red cabbage, blackberry juice, tea and universal indicator.

5. 7Ec
In the red
2 What colour would purple litmus go if you mixed it with: a) sulphuric acid
red
b) tap water
stay purple
c) lemon juice?

6. 7Ec
In the red
3 A few drops of litmus solution were added to some toothpaste. The litmus turned blue. What does this tell us about toothpaste?
Toothpaste is not an acid, it is an alkali.

7. 7Ec
In the red
4 Sally crushed up some purple berries from a bush, and mixed them with a little water. When she mixed the juice with some washing powder, it changed colour to red.
a) Is the berry juice acting as an indicator? Explain your answer.
Yes (probably) – it has changed colour when mixed with another chemical.

8. 7Ec
In the red
4 Sally crushed up some purple berries from a bush, and mixed them with a little water. When she mixed the juice with some washing powder, it changed colour to red.
b) Which of these best describes the washing powder? A-definitely an acid; B-definitely not an acid; C-possibly an acid. Explain your answer.

9. 7Ec
In the red
C – you cannot be certain on the evidence presented. Sally would have to test the juice with a known acid before interpreting the colour change.