According to which of the following laws, the pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases?

Dalton's Law

The correct answer is option 3. Dalton's Law.

Dalton's Law of partial pressures states that the total pressure exerted by a mixture of non-reacting gases is equal to the sum of the partial pressures of individual gases in the mixture. This law holds true as long as the gases behave ideally, meaning there are no significant intermolecular forces and the volumes of the gas particles are negligible compared to the volume of the container.