What is the total pressure in a mixture of gases equal to?

The total pressure in a mixture of gases is equal to the sum of all the individual gas partial pressures. This principle is rooted in Dalton's Law of Partial Pressures, which states that in a mixture of non-reacting gases, each gas exerts a pressure independently of the others.

Each gas in the mixture contributes to the overall pressure according to its partial pressure, which is defined as the pressure that gas would exert if it occupied the entire volume alone at the same temperature. Therefore, when calculating the total pressure, you simply add the partial pressures of all the gases present in the mixture.

This understanding is vital in various HVAC applications, including calculating the performance of refrigeration systems where different gases can be present, and ensuring system efficiency by understanding the behavior of gas mixtures under varying conditions.