What is the lightest element in the periodic table?

Which type of chemical reaction involves a substance combining with oxygen to release energy?

What is the name of the process by which a liquid changes to a gas at its boiling point?

What is the valency of carbon that makes it the basis of organic chemistry?

Which particle determines the chemical properties of an element?

Which acid is found naturally in vinegar?

Which gas has the chemical formula CO2?

What is the chemical formula for ammonia?

What is the atomic number of oxygen?

Which element is a liquid at room temperature and is used in thermometers?

Which law states that matter can neither be created nor destroyed in a chemical reaction?