Why is it difficult to classify dissolving as simply a physical or a chemical change?

Question

A. Some substances taste the same after they dissolve, and others do not.
B. Some substances keep the same molecular structure when they break down, and others do not.
C. Some substances keep the same color when they dissolve, and other do not.
D. Some substances release energy when they dissolve, and some absorb energy

Answer 1

The correct answer is B. Some substances keep the same molecular structure when they break down, and others do not.

Dissolving is complex because it can involve changes at the molecular level. In some cases, the solute maintains its molecular structure when it dissolves (like table salt in water), meaning it's merely a physical change. In other cases, the dissolving process can lead to a chemical change, where the solute interacts with the solvent at a molecular level, potentially forming new substances. Thus, determining whether dissolving is a physical or chemical change can be challenging.