A gas mixture with a total pressure of 745 mmHg contains each of the following gases at the indicated partial pressures: CO2, 125 mmHg; Ar, 214 mmHg; and O2, 187 mmHg. The mixture also contains helium gas. What is the partial pressure of the helium gas

219 mmHg

Explanation:

The partial pressure of a gas refers to the pressure exerted by one of the gases in a mixture of gases.

The total pressure of a gas is the sum of all the partial pressures of all the gases in the mixture.

Since the total pressure = 745 mmHg

The partial pressure of helium is;

745 - (125 + 214 + 187)

Partial Pressure of helium gas= 219 mmHg