Answer to Question #126160 in General Chemistry for mike

Question

A sample of limestone, CaCO3 was sealed inside a strong glass tube. The mass of the tube and limestone was found to be 156.4g. The tube was then heated over a Bunsen burner, causing the formation of some quicklime, CaO and carbon dioxide gas?

Answer 1

When $CaCO_3$ is strongly heated, it undergoes thermal decomposition to form $CaO$ and $CO_2$

The equation for the reaction is as follows;

$CaCO_3$ $_{(s)}$ $\to$ $CaO_{(s)}$ $+$ ${CO_2}_{(aq)}$

The mass of the products after the reaction is not affected by the reaction hence the products mass remains at $156.4g$ after the reaction.