The Exciting World of Gases: Exploring Behaviors and Predictions
What are some predicted behaviors of gases?
A. An air balloon gets bigger as it is warmed at constant pressure.
B. An air balloon gets bigger as it is cooled in a refrigerator.
C. An air balloon gets a higher internal pressure when more air is pumped into the balloon at constant pressure and temperature.
D. An air balloon is warmed when air is leaked out at constant pressure and volume.
E. An air balloon gets bigger as more air is pumped into the balloon at constant pressure and temperature.
Which of the following is not consistent with predicted behaviors of gases?
Answer:
The option stating that an air balloon gets bigger as it is cooled in a refrigerator is inconsistent with predicted behaviors of gases.
Heating gases leads to their expansion, whilst cooling results in their contraction. Increasing the air pumped into a balloon at constant temperature and pressure raises the internal pressure due to the increased number of gas particles.
Explanation: Answer choice B - An air balloon gets bigger as it is cooled in a refrigerator - is not consistent with the predicted behaviors of gases. According to the ideal gas law and Charles's Law, the volume of a gas is directly proportional to its temperature, given that pressure and the number of gas molecules remain constant. As such, when a gas is heated, it expands, and when it is cooled, it contracts. Therefore, an air balloon should actually get smaller when cooled and not bigger. This is inconsistent with the behaviour outlined in option B. Examples of the correct behavior may include that heating gases leads them to expand, which can raise a hot air balloon as seen in Figure 9.1. The relation also applies inversely, where upon cooling, gases contract, suggesting a balloon would shrink in a cooler environment like a refrigerator. Similarly, when more air is pumped into a balloon at constant pressure and temperature, it leads to a higher internal pressure due to an increase in the number of gas particles, as indicated in option C. Hence, defying these principles would go against the expected behavior of gases.
However, each situation assumes that all other factors, such as pressure or the number of gas particles, remain constant which might not always be the case in real-life situations.