William Henry made systematic studies of the solubility of a gas in a liquid. He gave a quantitative relationship between the solubility of a gas in a solvent and pressure which is known as Henry’s law. The law states that- the mass of a gas dissolved per unit volume of the solvent at a constant temperature is directly proportional to the pressure of the gas in equilibrium with the solution.

If m is the mass of the gas dissolved in a unit volume of the solvent and p is the pressure of the gas in equilibrium with the solution, then

\[m \propto p\]

\[or,  m = K.p\]

where K is the proportionality constant. The magnitude of K depends on the nature of the gas, the nature of the solvent, the temperature and the units of pressure. Thus, Henry’s law may also be stated as: the solubility of a gas in a liquid at a particular temperature is directly proportional to the pressure of the gas in equilibrium with the solution.

What are some important applications of Henry's law?

All of the above

The answer is 4. All of the above.

Henry's law has many important applications in a variety of fields, including:

• Packing soda cans: The solubility of carbon dioxide in water is directly proportional to the partial pressure of carbon dioxide above the water. This is why soda cans are sealed under high pressure, which ensures that a high concentration of carbon dioxide is dissolved in the water. When the can is opened, the pressure decreases and the carbon dioxide comes out of solution, forming bubbles.
• Respiration: The solubility of oxygen in blood is directly proportional to the partial pressure of oxygen in the air. This is why it is important to breathe deeply when you are exercising, as this increases the partial pressure of oxygen in the air and therefore increases the amount of oxygen that can be dissolved in the blood.
• Production of carbonated beverages: The production of carbonated beverages relies on Henry's law. The carbon dioxide is dissolved in the water under high pressure, and then the pressure is released. This causes the carbon dioxide to come out of solution, forming bubbles.

These are just a few of the many important applications of Henry's law. It is a fundamental law of chemistry that has a wide range of applications in many different fields.