Question

1. if you heat most earth substances, what happens to their density?

Explanation:

Step1: Recall density formula

Density $
ho=\frac{m}{V}$, where $m$ is mass and $V$ is volume.

Step2: Understand thermal - expansion

When most Earth substances are heated, they expand (volume $V$ increases) while mass $m$ remains constant (no mass is added or removed in a closed - system heating process).

Step3: Analyze density change

Since $
ho=\frac{m}{V}$ and $m$ is constant and $V$ increases, the density $
ho$ decreases.

Answer:

The density decreases.