Identical heat lamps are arranged to shine on identical containers of water and methanol (wood alcohol), so that each liquid absorbs the same amount of energy minute by minute. The covalent bonds of methanol molecules are non-polar, so there are no hydrogen bonds among methanol molecules. Which of the following graphs correctly describes what will happen to the temperature of the water and the methanol?

Question

Quizplus · Accepted Answer

Water has strong hydrogen bonding between its molecules, which allows it to absorb more heat energy per unit mass than methanol. This means that, even though the heat lamps are providing the same amount of energy to both liquids per minute, the temperature of the water will increase at a faster rate than the temperature of the methanol. The gradient of the line for water should be steeper than the gradient of the line for methanol. Choice B correctly represents this relationship.

Identical Heat Lamps Are Arranged to Shine on Identical Containers