A student examines how rapidly four metal carbonates break down. When metal carbonates are heated, they decompose and release a gas. The student proposes judging how readily different carbonates decompose by timing how long a sample of limewater takes to become milky, using the apparatus shown. The results of the investigation are shown in the table.
(a)[1]
Name the gas responsible for the limewater turning milky.
(b(i))[1]
To make the test fair, the heat supplied should be unchanged in each experiment. State how this could be achieved.
(b(ii))[2]
Suggest two other ways to make this investigation a fair test.
(c)[1]
Which one of the four metal carbonates decomposes the most rapidly?
(d)[2]
Another student says that one source of inaccuracy in this investigation is that deciding exactly when the limewater has turned milky is subjective. Explain how the investigation could be modified to give more accurate results.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “carbon dioxide gas ($\text{CO}_2$)” …