12g of iron oxide is produced in 120s, what is the reaction rate?
5cm3 of carbon dioxide product gas is produced in 30 minutes, what is the reaction rate?
2.4g of copper is used in a reaction lasting 2 hours, what is the rate of reaction?
Challenge: if I add 0.6M hydrochloric acid to calcium carbonate powder, what changes could I do to speed up the reaction?