Question

How many moles of gas are there in a sample occupying 1.74 L at 0.136 atm and 25°C? [1] 0.00968 mol

[2] 0.0463 mol

[3] 0.0926 mol

[4] 7.36 mol

[5] None of the above 

Answer 1

V = 1.74 L

P = 0.136 atm = 13.78 kPa

T = 25°C = 298 K

R — universal gas constant = 8.31

n = ?

Clapeyron equation:

$PV= nRT$

$n = ~\cfrac {PV}{RT}=~ \cfrac {13.78*1.74}{8.31*298}= ~\bold{0.00968~ mol}$

Answer: [1] 0.00968 mol