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