How does pressure affect the solubility of gases in liquids?

Pressure directly affects the solubility of gases in liquids; an increase in pressure increases gas solubility.

In more detail, the relationship between pressure and the solubility of gases in liquids is governed by Henry's Law. This law states that at a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the pressure of that gas above the liquid. In simpler terms, if you increase the pressure of a gas above a liquid, more gas molecules will dissolve in the liquid.

This is because increasing the pressure forces more gas molecules into the liquid. Imagine a container filled with a liquid and a gas above it. If you increase the pressure in the container, you're essentially squeezing more gas molecules into the space above the liquid. Some of these gas molecules will collide with the liquid surface and get 'trapped' inside, increasing the solubility of the gas.

This principle is used in many practical applications. For example, in the production of fizzy drinks, carbon dioxide gas is dissolved in the drink under high pressure. When the bottle or can is opened, the pressure is released, allowing the gas to come out of the solution and create the fizz.

However, it's important to note that this relationship only holds true for gases. The solubility of solids in liquids is not affected by pressure. This is because solids have a definite shape and volume, and increasing pressure doesn't force more solid particles into the liquid.

Remember, understanding the relationship between pressure and solubility is key to mastering this aspect of chemistry. It's not just a theoretical concept, but a practical one that's used in everyday life.