[问答题]
1.Outline how a gas exerts pressure on a surface.
2.1.A balloon containing helium gas is released from the ground. The pressure exerted by the helium is approximately equal to the pressure exerted by surrounding air. The balloon expands at constant temperature as it rises.
The balloon contains $16$ of helium (molar mass $4.0gmol^−1$), has a temperature $T$ of $300K$ and a pressure $P_0$ of $100kPa$ at ground level.
Calculate the volume $V_0$ of the balloon at ground level.
22.At heights much less than 10 km, the pressure $P$ inside the balloon is related to its height ℎh (in $m$) by the approximation
$P≈P_0(1−\frac{h}{10km})$
The balloon ascends until its volume is 5% higher than the volume at ground level.
Estimate the new height of the balloon.
Estimate the new height of the balloon.
3.The same balloon at $100kPa$ is placed inside a sealed, rigid container of volume $3V_0$ and a temperature of $300K$. A pump is used to remove air from the container. When the air remaining in the container consists of half as many molecules as the number of molecules inside the balloon, the balloon bursts.
Determine the pressure inside the container at the moment the balloon bursts.
