Consider a mixture of two gases A and B, confined to a closed vessel. A quantity of a third gas, C, is added to the same vessel at the same temperature. How does the addition of gas C affect the total pressure in the vessel?

Total pressure increased

Explanation:

When gas C is added in the vessel then number of mole increases and number of collision depends on the number of molecules present in the vessel and on adding gas C, mole also increases hence number of collision increases therefore pressure also increases because number of collision increases.

Total pressure increases.