Chapter 14, Problem 49A

Interpretation Introduction

Interpretation: To describe what happens to the volume of a balloon when it is taken outside on a cold winter day.

Concept Introduction: A theoretical gas called an ideal gas is made up of several independently moving point particles without any interparticle interactions. Because it adheres to the ideal gas rule, the ideal gas concept is helpful.

Answer to Problem 49A

The balloon shrinks because of the cooler air's decreased energy.

Explanation of Solution

The volume of the balloon decreases because the gas within cools down as a result of the cold temperature. Because helium is lighter than the same volume of air at room temperature, the helium balloon rises. It is heavier because it has a lower capacity at low temperatures than air would.

As a result of the cooler air's lower energy, the balloon contracts.