Question

1. your lab instructor gives you a red solid and tells you that it is a pure substance. which of (3pts) the following statements is true given this information? the solid has a fixed composition by mass. the solid is a compound. the solid cannot be decomposed into simpler substances. the solid cannot be melted.

Explanation:

A pure substance (element or compound) has a fixed, consistent composition by mass. A pure solid could be an element (which cannot be decomposed) or a compound (which can be decomposed), and all pure solids can be melted with sufficient heat. Only the statement about fixed composition applies to all pure substances.

Answer:

The solid has a fixed composition by mass.