Question

Two substances have the same mass and are both initially at 200°C. They both absorb 150 J of energy. Which substance will have the higher temperature, the one with the higher or the lower specific heat?

Answer 1

The one with the lower specific heat.

Explanation:

A substance's specific heat tells you how much heat must be added to / removed from a `"1-g"` sample of this substance in order to get its temperature to change by `1^@"C"`.

When energy in the form of heat is absorbed, a substance's specific heat tells you exactl;y how much heat is needed in order to increase the temperature of `"1 g"` of this substance by `1^@"C"`.

This means that the higher the specific heat of a substance, the more heat will be needed in order to get the temperature of `"1 g"` to increase by `1^@"C"`.

In your case, two substances, let's say `A` and `B`, start at the temperature, `200^@"C"` and they both absorb `"150 J"` of heat. Moreover, they both have the same mass.

If the specific heat of `A` is higher than the specific heat of `B`, you can say that it will take more energy to raise the temperature of `A` by `1^@"C"` than to raise the temperature of `B` by `1^@"C"`.

So, if `B` absorbs `"150 J"` and gets to a final temperature `T_B`, the fact that `A` has a higher specific heat will tell you that absorbing `"150 J"` of heat will not get the final temperature of `A`, `T_A`, to the same value as `T_B`.

You can thus say that

`T_A < T_B`

The substance with the lower specific heat will heat up more than the substance with the higher specific heat.