Chapter 17, Problem 100A

Interpretation Introduction

Interpretation: The reason why burning from steam is more serious than a burn from hot water is to be evaluated.

Concept Introduction : Latent heat of vaporization is the amount of heat energy required to change the phase from liquid to vapor.

Answer to Problem 100A

The burn from steam is more serious than a burn from water because steam has more heat content and also due to the heat released when steam condenses on the cold skin.

Explanation of Solution

The heat supplied to liquid results in the rise of temperature until the boiling point is reached. After this point, heat is continuously added but without a rise in temperature, which results in steam having a higher energy content than hot water.

Also, when water changes to steam, energy is absorbed from surroundings, and when the steam comes in contact with cold skin, it condenses back into its liquid form, the latent energy which was consumed during vaporization is now released.