Question

Expansion during heating

• A. Occurs only in solids.
• B. Decreases the density of the mate
• C. Occurs at the same rate for all liquids and gases
• D. IncreasesThe weight of the material

Answer 1

Answer: (B)

Decreases the density of the mate

Answer 2

Density is mass divided by volume. As you heat something up the volume increases so the density decreases. Water is a bad example, it does not follow the standard rules. Its volume is smallest at about $4^{\circ} C$. As you cool or heat it from this point the water will expand. This is why ice floats, whereas most solids will sink on their corresponding liquid state.