Question

The density of copper decreases as temperature increases (as does the density of most substances). Which change occurs in a sample of copper when it is warmed from room temperature to 95 °C?
(a) The sample will become lighter.
(b) The sample will become heavier.
(c) The sample will expand.
(d) The sample will contract.

Answer 1

Answer: Option (c) is the correct answer.

Explanation:

As we know that density the amount of mass present in per unit volume.

Mathematically,      Density = $\frac{mass}{volume}$

So, it means that density is inversely proportional to volume. Hence, when there will be decrease in density of a substance then there will be increase in its volume. That is, expansion of substance will take place.

Also, boiling point of copper is 2,562 degree celsius but we are heating it up to a temperature of 95 degree celsius. This means that copper will remain in liquid state at this temperature.

Thus, we can conclude that a change which occurs in a sample of copper is that copper sample will expand.