# A sample of gas is collected over water at a temperature of 35.0°C when the barometric pressure reading is 742.0 torr. What is the partial pressure of the dry gas?

This site tells me that vapour pressure of water at $35.0$ ""^@C $=$ $42.2 \cdot m m \cdot H g$.
${P}_{\text{collected}}$ $=$ ${P}_{\text{gas" + P_"SVP}}$, ${P}_{\text{SVP}}$ is given above, and is called the saturated vapour pressure. This should have been quoted with the question.
Thus ${P}_{\text{gas}} \cong 700 \cdot m m \cdot H g$.