When an old building is to be torn down, Mr. Pham’s company removes the bricks, cleans off the mortar from the bricks, and then sells the bricks to companies that restore historic buildings. Which compound is Mr. Pham’s company most likely to use in its work?

The company needs to remove mortar from bricks. Mortar commonly contains calcium carbonate, which reacts with hydrochloric acid and dissolves, helping clean the bricks. Sodium hydroxide and lithium hydroxide are bases, while nitric acid is less likely to be used for this cleaning task. The best choice is hydrochloric acid.

AI-written and checked against the verified answer.