a solution or paper that will turn different colours depending on pH of the solution.

is a scale from 1 to 14 used to measure the acidity or alkalinity of solutions. pH7 is for neutral solutions.

are tools used to crush and grind substances. The pestle is a grinding club and the mortar a heavy bowl.

is a chemical that will change colour to indicate the presence of a substance, for example if a solution is an acid or alkali.

formed when a substance dissolves into a liquid.

Practical: red cabbage indicator solution

Science

In the unit Making salts, pupils will build on this knowledge to learn about the production of pure salts, and about why acids are acidic and how bases can neutralise them. 

In the Understanding Chemical Reactions unit, pupils learned how atoms rearrange to form new substances during chemical reactions.

Acids and bases

Physical activity and equipment requiring safe use

Use green cabbage instead of red cabbage.

A pupil uses red cabbage to make an indicator. The solution produced is too pale to show a colour change. How could the method to make the indicator be improved?

Which of the following describe what a mortar and pestle are used for?

Match the following colours of red cabbage indicator to the correct type of the substance.

Litmus does not clearly indicate when a solution is pH 7.

Red cabbage does not indicate when a solution is pH 7.

Universal indicator turns a different colour for each pH from 1 to 14.

Red and blue litmus are more effective as indicators of pH than red cabbage.

Which of the following statements explain why red cabbage and litmus are less effective than universal indicator at indicating the pH of a substance? 

Different chemical indicators turn different colours at the same pH. Match the colour to the correct indicator if a solution has a pH of 7.

A soluble substance dissolves in a solvent.  If the solvent is water, what name is given to a soluble base?

Match the following keywords to the correct description.

The mixture formed when a solid dissolves in a liquid.

The ability of a substance to dissolve in a liquid.

A liquid in which a substance will not dissolve.

Which of the following statements about solvents is correct?

Which two of the following keywords can be used to describe a substance that can dissolve in a liquid?

Some pH scales have a range from 0 to 14. Which of the following would describe a substance with a pH of 0?

The sum of the maximum and minimum values.

The difference between the maximum and minimum values.

The pH range most commonly used is from 1 to 14. What does the term 'range' mean?

The lower the concentration of hydrogen ions in a solution, the {{}} the pH of the solution.

Content guidance

Risk assessment required - equipment

Adult supervision required

Starter Quiz