A student is studying how concentration affects the rate of reaction between calcium carbonate and hydrochloric acid. He uses the method below. • Put 1 g of calcium carbonate into a conical flask. • Add excess hydrochloric acid. • Allow the reaction to carry on until no more gas is produced. • Carry out the experiment again using hydrochloric acid at different concentrations. Which important step is missing from the method if he wants to calculate the rate of reaction?
- Aheating the reaction mixture
- Bplacing a bung in the flask
- Ctiming the reaction
- Dusing a catalyst