Primary Checkpoint. 2026. Science (0097). May - Paper 2 - Question 5

Ahmed makes a lemon volcano.

Ahmed:

- puts half a lemon onto a large plate
- puts a thermometer into the lemon
- measures the temperature of the lemon
- covers the lemon with sodium bicarbonate
- measures the temperature again.

Ahmed labels a picture to show his experiment and his results.



Complete the sentences about the lemon volcano investigation.

Use the picture to help you.

**(a)** The citric acid reacts with ___ .