In caves, dripping groundwater containing calcium bicarbonate can form stalactites and stalagmites. when the water is exposed to air, some of the calcium bicarbonate turns into calcium carbonate, which gets deposited on the ground. what makes this process a chemical change?

This question comes with these answer choices:

A. A new substance is formed in this process, which is an important clue to chemical change.

B. A change in state is observed in this process, which is an important clue to chemical change.

C. This process involves separation of dissolved substances, which is an an important clue to chemical change.

D. This process involves dissolving substances together, which is an an important clue to chemical change.

E. This process involves breaking and reshaping of substances, which is an an important clue to chemical change.

option A. A new substance is formed in this process, which is an important clue to chemical change.

Justification:

A chemical change or chemical reaction is a process where one or more substances are involved in the creation of a new substance.

In this case, it is calcium bicarbonate (Ca(HCO₃)₂) that reacts with oxygen to create calcium carbonate (CaCO₃). Calcicum carbonate is a different substance than calcium bicarbonate. Each one has its proper unique chemical composition different from each other: