Why can gases liquefy under high pressure?

Gases can liquefy under high pressure because it forces the gas particles closer together, enabling intermolecular forces to take effect.

In a gas, the particles are spread out and move freely at high speeds. They have a lot of kinetic energy, which overcomes the intermolecular forces of attraction between them. This is why gases have no fixed shape or volume and can expand to fill any container. However, when you apply pressure to a gas, you are essentially forcing the particles to move closer together.

Under high pressure, the volume of the gas decreases. This is because the particles are being squeezed into a smaller space. As the particles get closer together, the intermolecular forces of attraction between them start to take effect. These forces pull the particles together and hold them in place, which is the characteristic of a liquid. This process is known as liquefaction.

The ability of a gas to liquefy under pressure also depends on the temperature. If the temperature is too high, the kinetic energy of the gas particles will be too great for the intermolecular forces to hold them together, even under high pressure. Therefore, for a gas to liquefy, the temperature must be low enough for the intermolecular forces to take effect.

In summary, gases can liquefy under high pressure because it decreases their volume and brings the particles closer together. This allows the intermolecular forces of attraction to hold the particles in place, turning the gas into a liquid. However, the temperature must also be low enough for this to happen.