Question

A balloon is inflated with roomtemperature air and then put in a sunny place. The balloon expands slightly due to a rise in temperature.Which of the following best describes the molecules of air inside the balloon when the balloon is left in the sunlight as compared to when it was first inflated?

a. The molecules are moving faster.
b. There are more molecules in the balloon.
c. There are fewer interactions between the molecules.
d. The molecules stop colliding with the walls of the balloon.

Answer 1

The a, molecules of air inside a balloon that is exposed to sunlight move faster as the temperature rises, according to kinetic molecular theory, which leads to the expansion of the balloon.

Step-by-step explanation:

When a balloon is left in the sunlight after being inflated with room-temperature air, the molecules of air inside the balloon expand as the temperature increases. This can be best described by saying that the molecules are moving faster. The principles of kinetic molecular theory inform us that as temperature rises, the average kinetic energy of the gas particles increases. Consequently, this increased energy results in the gas particles moving at higher speeds and striking the walls of the balloon more forcefully, which is what leads to the expansion of the balloon.

The pressure inside a hot air balloon is similarly affected by temperature changes. As the air inside the balloon heats up, the movement of the molecules speeds up, and they impact the balloon's walls with greater force, causing an increase in pressure. This is what allows hot air balloons to move smoothly in the air, as they create a buoyant force by becoming less dense than the air outside. This same principle explains why the balloon expands when placed in sunlight.