How much?

What is an atom's atomic number and mass number?

What are the relative masses of protons and neutrons?

What are isotopes?

How can we calculate the relative formula mass of a compound from the elements?

What do balanced symbol equations tell us about chemical reactions?

What does the yield of a chemical reaction describe?

What are the factors affecting the yield of a chemical reaction?

Why is it important to achieve a high yield in industry and to waste as little energy as possible?

What is a reversible reaction?

What are food additives?

How can we identify food additives?

Gas chromatography

Mass spectrometer