1.) Gas Number of moles N2 3.10 O2 0.76 CO2 0.12 If the total pressure is 1.07 a
ID: 946796 • Letter: 1
Question
1.)
Gas Number of moles
N2 3.10
O2 0.76
CO2 0.12
If the total pressure is 1.07 atm, what is the partial pressure of Oxygen? (Your answer will be in atmospheres, but do NOT include units - Blackboard won't allow them. Use two decimal places, and simply give the number portion.)
2.) A reaction is carried out that produces hydrogen gas. The gas is collected in an inverted beaker over water at 25 oC. The vapor pressure of water at 25 oC is 23.78 mmHg. The total pressure in the beaker is determined to be 755.3 torr. What is the partial pressure (in units of torr) of the hydrogen gas in the beaker?
Explanation / Answer
(1) Total number of moles,N = number of moles of N2 + Number of moles of O2 + Number of moles of CO2
= 3.10 + 0.76 +0.12
= 3.98 moles
Mole fraction of Oxygen , X = number of moles of Oxygen / Total number of moles
= 0.76 / 3.98
= 0.191
Partial pressure of Oxygen , p = mole fraction of oxygen x total pressure
= 0.191 x 1.07 atm
= 0.20 atm
Therefore the partial pressure of Oxygen is 0.20 atm
(2) Given total pressure , P = 755.3 torr
Vapour pressure of water , pH2O = 23.78 mm Hg = 23.78 torr Since 1 torr = 1 mm Hg
Total pressure , P = vapour pressure of water + Partial pressure of H2
So Partial pressure of H2 = P - pH2O
= 755.3 - 23.78
= 731.5 torr
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.