Question

State Henry's law.

Short answer

Henry's law states that gas solubility in a liquid is proportional to the gas's partial pressure.

Step-by-step solution

Define Henry's Law

Henry's law states that at a constant temperature, the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of that gas in contact with the liquid."

Express in Mathematical Form

The law can be mathematically expressed as: \[ C = kP \]where \( C \) is the concentration of the gas in the liquid, \( P \) is the partial pressure of the gas above the liquid, and \( k \) is the Henry's law constant which varies for different gases.

Identify Key Components

In Henry's law, the key components are concentration of gas in the solvent (\( C \)), its partial pressure (\( P \)), and the Henry's law constant (\( k \)), which is a measure of the gas's solubility in the given liquid.

Key concepts

Gas Solubility

Gas solubility refers to how well a gas can dissolve into a liquid. This process depends on various factors, including the nature of the gas and the liquid, as well as the temperature and pressure conditions. When gas molecules are introduced to a liquid, they interact with the liquid's molecules, forming a solution.

• The more soluble a gas is, the more molecules can integrate within the liquid.
• The solubility often decreases with an increase in temperature, meaning gases are usually less soluble in warmer liquids.

Henry's Law plays a crucial role in determining this property by stating that, at a constant temperature, the solubility of a gas in a liquid is proportional to the partial pressure of that gas in contact with the liquid. Therefore, increasing the pressure increases the gas's solubility.

Partial Pressure

Partial pressure is a concept used to describe the pressure exerted by a single type of gas in a mixture of gases. In other words, it’s the hypothetical pressure that this gas would exhibit if it alone occupied the entire volume.

• This pressure is crucial when discussing gas behavior in solutions as outlined by Henry's Law.
• When a gas is in contact with a liquid, its partial pressure will affect how much of it dissolves into the liquid.

In practice, if the partial pressure of a gas above a liquid increases, more gas molecules will be forced into the liquid, increasing its solubility. For example, this principle is why carbonated beverages remain fizzy under pressure in a sealed container.

Concentration of Gas in Liquid

The concentration of a gas in a liquid is a measure of how many molecules of the gas are present in a given volume of the liquid. Henry's Law represents this relationship using the formula: \[ C = kP \]where:- \( C \) is the concentration of the gas in the liquid,- \( P \) is the partial pressure of the gas,- \( k \) is Henry's law constant for the gas-liquid combination.This formula shows that the concentration (\( C \)) is directly proportional to the partial pressure (\( P \)) of the gas, multiplied by a constant (\( k \)) that depends on the specific gas and liquid involved.

• The constant \( k \) varies depending on the type of gas and the solvent, reflecting how different gases dissolve at different rates.
• Understanding this relationship helps in predicting how much gas will dissolve when the partial pressure changes.

This principle is fundamental in fields such as environmental science, medicine, and engineering, where controlling the concentration of gases in liquids is often crucial.