The Exciting Science of Balloons and Temperature Changes!
What happens when a balloon with 1000 cm3 of air is taken from 20°C indoors to 10°C outside with constant pressure?
Which of the following descriptions are correct for the air inside the balloon in this scenario?
- When the balloon is outside the house, it has a volume less than 1000 cm^3.
- When the balloon is outside the house, it has a volume greater than 1000 cm^3.
- Heat energy was added to the air in the balloon.
- Heat energy was removed from the air in the balloon.
- The air in the balloon did work on the atmosphere.
- The atmosphere did work on the air in the balloon.
Answer:
The first option is correct.
Heat energy was removed from the air in the balloon.
The air in the balloon did work on the atmosphere.
The correct description for what happens when a balloon with 1000 cm^3 of air is taken from 20°C indoors to 10°C outside, while maintaining constant pressure, is that the balloon's volume will decrease and heat energy is removed from the air in the balloon. No work is done by or on the gas in the balloon.
When the balloon filled with 1000 cm^3 of air is taken from a warmer environment (20°C) to a cooler one (10°C), and if we assume the pressure remains constant, according to Charles's Law, the volume of the air in the balloon would decrease. Therefore, the correct description is that when the balloon is outside the house, it has a volume less than 1000 cm^3. The decrease in temperature means that heat energy was removed from the air in the balloon. Since the question implies constant pressure and it does not mention that the balloon is expanding or contracting actively, there is no work being done by or on the gas, so the last two options about the balloon doing work on the atmosphere or vice versa would not apply.