What does Dalton's Law of partial pressures state?

Dalton's Law of partial pressures states that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each individual gas present in that mixture. This means that if you have several gases in a container, each gas contributes to the total pressure according to its own pressure exerted, known as its partial pressure.

For instance, if you have oxygen, nitrogen, and carbon dioxide in a container, you can measure the pressure exerted by each of these gases separately. When you add up these individual pressures, you get the total pressure exerted in the container. This principle is crucial in understanding gas behavior, especially in mixtures, and allows scientists to predict how changes in conditions will affect the pressure of individual gases.

The other options do not correctly reflect the law's principle: one implies that each gas has the same pressure as the total, another suggests pressure is independent of the number of gases, and the last states an incorrect relationship between pressure and the number of moles. Understanding Dalton's Law is fundamental for any further studies in gas behavior and chemistry as a whole.