Question

Some hydrogen gas is collected over water at 20.0 Cel. and the levels inside the container is the same. The partial pressure of hydrogen is 742.5 torr. What is the barometric pressure as the time the gas was collected.
My answer is 742.5 torr = 17.5 torr = 760 torr. Am I correct. thanks

Answer 1

No and yes.
Ptotal = pH2 + pH2O.
pH2 is given as 742.5
I assume you looked up the vapor pressure of H2O at 20 C and found 17.5 torr.
So 742.5 + 17.5 = 760.
I think you just made a typo and hit = instead of +.