Question

Two students investigated the relationship between the density of water and its temperature. The students put a fixed mass of water in a small-diameter glass tube attached to a flask. This enabled them to measure the change in the volume of the water as the temperature was increased by heating the flask in a container of oil. The students then calculated the density of the water at each temperature and represented their data on this graph.

The highest temperature for which they collected data was 80º Celsius. If another reading of volume is made when the temperature is increased to 85º Celsius, what density would be expected?


(A)The density of water will remain unchanged.


(B) The density of the water will be less as the temperature is increased.


(C)The density of the water will be greater as the temperature is increased.


(D)The density change would be impossible to predict as the temperature is increased.

Answer 1

Based on the typical behavior of water, we can expect that the density of the water will decrease as the temperature is increased from 80º Celsius to 85º Celsius. This is because water expands as it is heated, which means that the volume of the water will increase even though the mass remains the same. As a result, the density (mass/volume) will decrease.

Therefore, the answer is (B) The density of the water will be less as the temperature is increased.