Question

How many grams of Hydrogen (H2) are in a tank with a gauge pressure of 2 atmospheres, a volume of 14 liters and a temperature of 90 degrees C. (Atomic Mass of Hydrogen (H) is 1 g/mol)

11.36825 grams

2.81741 grams

1.878273 grams

7.578833 grams

Answer 1

The problem can be solved using ideal gas equation

P*V=n*R*T

Where, P is pressure in Pascal, V is volume, n is number of moles, R is universal gas constant, T is temperature in Kelvin

In the given problem, P=2 atm=2*10^5 Pascal

V=14 liters=14*10^-3 m³

R=8.314 J/ K*mole

T=90 degrees C=90+273=363 Kelvin

2*10^5*14*10^-3=n*8.314*363

n=0.928

Molar mass of hydrogen gas=2.014 gm

Number of moles=mass of gas/molar mass

0.928=mass of hydrogen gas/2.014

Mass if hydrogen gas=0.928*2.014=1.87 gm

Third option is correct