压强-体积
读数
发生了什么
气体压强其实就是粒子不断撞击容器壁。加热让粒子运动得更快（撞得更多、更重），压缩让同样的撞击集中在更小的壁面上。实测压强（根据实际的撞壁次数统计并平滑处理）与理想气体的预测 P = nRT/V 一致，后者就是图上的曲线。
- Ideal gas equationPV = nRT
考试大纲
- GCSE Physics AQA 4.3.3particle model and gas pressure
- GCSE and A-Level Chemistry and Physics AQA 3.6.2the ideal gas equation and kinetic theory
挑战
先预测：温度不变时把体积减半，压强会正好加倍吗？对照理想曲线观察实测点。
会。温度不变时 P ∝ 1/V（玻意耳定律），所以体积减半，理想压强正好加倍；实测点会在它附近上下波动。
系统地学
GCSE Combined and Separate Science 中讲这个主题的课：先看分步讲解，再做考试风格的题目，每次数字都不同。 课程为英文。
常见问题
What is Boyle's law?
At constant temperature the pressure of a fixed amount of gas is inversely proportional to its volume, so PV stays constant. Halve the volume and the pressure doubles.
Why does heating a gas raise its pressure?
Hotter particles move faster, so they hit the walls more often and harder. At constant volume the pressure is proportional to the absolute temperature in kelvin.
Why must temperature be in kelvin?
The gas laws are proportional to absolute temperature, which starts at absolute zero (0 K = −273.15 °C). Using °C would give zero or negative pressures at ordinary temperatures.
How do I find the new temperature of a gas with the combined gas law?
Rearrange P₁V₁/T₁ = P₂V₂/T₂ to T₂ = P₂V₂T₁/(P₁V₁), with temperatures in kelvin. Gas at 100 kPa, 2.0 L and 300 K squeezed to 1.5 L at 150 kPa ends at T₂ = 150 × 1.5 × 300 / (100 × 2.0) = 337.5 K, which is 64.4 °C. Pick Temperature T₂ under Solve for to see each step.