이상기체방정식과 부분 압력

이상기체방정식과 부분 압력

 

 

A sample of carbon monoxide gas was collected in 2.0 L flask by displacing water at 28 °C and 810 mmHg. Calculate the number of CO molecules in the flask. The vapor pressure of water at 28°C is 28.3 mmHg.

 

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CO의 분압 = 전체 압력 - H2O의 분압

= 810 mmHg - 28.3 mmHg = 781.7 mmHg

 

781.7 mmHg × (1 atm / 760 mmHg) = 1.029 atm

 

P = 1.029 atm

V = 2.0 L

R = 0.0821 atm•L/mol•K

T = 28 + 273 = 301 K

 

PV = nRT

n = PV / RT

= [(1.029)(2.0)] / [(0.0821)(301)]

= 0.08328 mol CO

 

1 mol = 6.02×10^23 molecules

0.08328 mol × (6.02×10^23 molecules / 1 mol)

= 5.0135×10^22 molecules

 

답: 5.0×10^22 molecules