Lucy is finding out if the speed of the reaction between solid calcium carbonate and acid changes if she uses different sized pieces of the solid. Which of these statements is correct?

Jermaine repeats a reaction 5 times when he is investigating exothermic reactions. These are the temperature changes he records: 10.4 °C, 10.8 °C, 10.5 °C, 11.0 °C, 10.7 °C Which word could be used to describe his results?

Scientists use standard symbols to represent elements and compounds. Write down the formulae for these substances:

Which word describes a change from particles being widely spaced and moving around freely, to moving around very close to each other?

Which technique would you use to separate two liquids with different boiling points?