Question

crayons were left out in the sun and melted. what kind of change does this demonstrate? a physical change a mass change a chemical change a reactivity change

Explanation:

A physical change is a change in which no new substances are formed. When crayons melt, they change from a solid to a liquid state. But the chemical composition of the crayon material remains the same. There is no new substance created. A mass change is not a standard type of change in this context. A chemical change would involve a reaction where new substances are formed (e.g., burning, rusting). Reactivity change is not relevant here as it refers to how readily a substance undergoes a chemical reaction, not the type of change (physical or chemical) when melting.

Answer:

a physical change