Final answer:
When a balloon absorbs heat while expanding, its internal energy and the average kinetic energy of gas particles increase, leading to an increase in temperature, which is consistent with Charles's Law.
Step-by-step explanation:
The question at hand asks whether the temperature of a balloon that is expanding from 5L to 10L against an outside pressure of 1 bar while absorbing 500J of heat increases, decreases, stays the same, or if more information is needed to determine the temperature change.
According to the principles of thermodynamics, the internal energy of a gas is linked to its temperature. When a gas absorbs heat, its internal energy tends to increase. Assuming that no energy is lost, the average kinetic energy of the gas particles would increase, which implies that the temperature of the gas increases as well. This thermal expansion is consistent with Charles's Law, which states that at a constant pressure, the volume of a gas increases as the temperature increases. Therefore, answer option C (Increases) is correct in this scenario.