Which term describes a change in a substance that does not involve a change in the identity of the substance?

Which term describes a change in a substance that does not involve a change in the identity of the substance?

• A. Physical Change
• B. Chemical Change
• C. Endothermic reaction
• D. Neutralization

Answer: (A)

Physical change is the idea that a substance changes form or appearance without changing its chemical identity. So, even if ice melts into liquid water, or sugar dissolves in water, the substance remains the same chemically—the molecules are still water or sugar, just arranged differently or dispersed. That’s what makes it a physical change: no new substance is formed. The other terms describe processes that do change what the substance is. A chemical change involves making or breaking bonds to produce new substances, so the identity changes. Endothermic reaction refers to a chemical change that absorbs heat, and neutralization is a chemical reaction between an acid and a base that forms new substances like salt and water.

Physical change is the idea that a substance changes form or appearance without changing its chemical identity. So, even if ice melts into liquid water, or sugar dissolves in water, the substance remains the same chemically—the molecules are still water or sugar, just arranged differently or dispersed. That’s what makes it a physical change: no new substance is formed.

The other terms describe processes that do change what the substance is. A chemical change involves making or breaking bonds to produce new substances, so the identity changes. Endothermic reaction refers to a chemical change that absorbs heat, and neutralization is a chemical reaction between an acid and a base that forms new substances like salt and water.