00:01
To determine the hydrogen pressure, ph 2, we'll take the barometric pressure, 741 .6 mmhg, subtract off the hydrostatic pressure, which is going to be the height of the burette in millimeters, so the liquid measured to be 174 mm, and we divide that by 13 .6.
00:33
And then we subtract off the vapor pressure of water at 298 kelvin.
00:45
They didn't give that to us, so we'll have to look it up.
00:48
The vapor pressure of water at 298, or 25 degrees celsius, is 23 .76 millimeters of mercury.
01:03
And we get 705 .0 millimeters of mercury, but they wanted in atmospheres.
01:20
So to convert it to atmospheres we divide by 760 and we get 0 .9277 atmospheres.
01:42
Then to find the moles of hydrogen gas.
01:47
Use the ideal gas law and calculate the moles...