The entire volume of a balloon is filled with air. However, over time, the balloon becomes soft as the air pressure inside it decreases.
According to the gas laws, which answer choice best describes the cause for the decrease in the balloon's air pressure?
a.The temperature of the air within the balloon increased, which caused the air particles to speed up and move farther apart.
b.The temperature of the air within the balloon decreased, which caused the air particles to slow down and move closer together.
c.The volume of the air within the balloon decreased, which caused the air particles to become cooler and slow down.
d.The volume of the air within the balloon increased, which caused the air particles to become warmer and speed up.
P V = n R T
V about the same
n the same
R the same
P down so T ?
To determine the cause for the decrease in the balloon's air pressure, we can refer to the gas laws, specifically the ideal gas law. The ideal gas law equation is PV = nRT, where P represents pressure, V represents volume, n represents the number of moles of gas, R is the ideal gas constant, and T represents temperature.
In this case, we are concerned with the change in air pressure inside the balloon, so we can focus on the variables P (pressure), V (volume), and T (temperature).
Looking at the possible answer choices:
a. The temperature of the air within the balloon increased, which caused the air particles to speed up and move farther apart.
In this scenario, if the temperature increased, according to the ideal gas law, the pressure would increase assuming the volume and the number of moles of gas remain constant. Therefore, option (a) does not best describe the cause for the decrease in the balloon's air pressure.
b. The temperature of the air within the balloon decreased, which caused the air particles to slow down and move closer together.
In this case, if the temperature decreased, according to the ideal gas law, the pressure would also decrease assuming the volume and the number of moles of gas remain constant. Thus, option (b) best describes the cause for the decrease in the balloon's air pressure.
c. The volume of the air within the balloon decreased, which caused the air particles to become cooler and slow down.
Here, the change in volume does not directly affect the temperature of the air particles. Instead, the volume affects the pressure according to the ideal gas law, but not the temperature. Hence, option (c) is not a suitable choice.
d. The volume of the air within the balloon increased, which caused the air particles to become warmer and speed up.
Similar to option (c), the change in volume does not directly impact the temperature of the air particles. The volume affects the pressure, not the temperature. Therefore, option (d) is not the correct choice either.
In conclusion, the correct answer is option (b). The temperature of the air within the balloon decreased, which caused the air particles to slow down and move closer together, resulting in a decrease in the balloon's air pressure.