Chemistry · May / June 2022 · Paper 12 · Question 26

Three dilute solutions of acid, each with a concentration of 0.01 mol / dm3, are reacted separately with excess calcium carbonate until there is no further reaction. The same volume of acid is used each time. The carbon dioxide produced is collected and its volume measured. All measurements are at room temperature and pressure. acid | pH | volume of carbon dioxide formed / cm3 1 | 2.0 | 20 2 | 1.7 | 40 3 | 3.4 | 20 What are the possible identities of the acids?

1. Ahydrochloric | sulfuric | ethanoic
2. Bhydrochloric | nitric | ethanoic
3. Cnitric | sulfuric | hydrochloric
4. Dsulfuric | hydrochloric | nitric

As printed in the paper