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Gas pressure and temperature
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Gas particles move randomly and hit the walls of their container. That is what causes gas pressure.
Pressure from particles
Gas particles move quickly in random directions. When they collide with the walls, they exert a force. Force over an area is pressure.
More collisions per second, or harder collisions, means more pressure.
More collisions per second, or harder collisions, means more pressure.
Temperature and absolute zero
Heating a gas makes its particles move faster, so at constant volume the pressure rises.
Absolute zero is −273 °C: the lowest possible temperature, when particles have the least possible kinetic energy.
Kelvin = °C + 273. The average kinetic energy of particles is proportional to the Kelvin temperature.
Absolute zero is −273 °C: the lowest possible temperature, when particles have the least possible kinetic energy.
Kelvin = °C + 273. The average kinetic energy of particles is proportional to the Kelvin temperature.
Volume and pressure (Separate Physics)
At constant temperature, squashing a gas into a smaller volume means more collisions with the walls each second, so the pressure goes up.
p1 × V1 = p2 × V2.
Doing work on a gas (e.g. pumping a tyre) can raise its temperature.
p1 × V1 = p2 × V2.
Doing work on a gas (e.g. pumping a tyre) can raise its temperature.
Convert 27 °C to kelvin.
- K = °C + 273
- 27 + 273
Answer: 300 K
Gas pressure comes from particles hitting the walls. Hotter means faster particles and higher pressure. Absolute zero is −273 °C (0 K). p1V1 = p2V2 at constant temperature.
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