Question

(PA41)

The reaction of hydrogen gas with oxygen gas is likely responsible for the Hindenburg disaster in 1937, when a airship filled with hydrogen gas ignited and burned, killing 37 people.

If 616 g of oxygen gas reacts completely with hydrogen gas, what volume of water vapor will be produced (in L) at 0.952 atm and 308°C ? Write the balanced equation to help you solve this problem.

Answer 1

Balanced chemical reaction is

2H₂ + O₂   $\rightarrow$ 2H₂O

molar mass of O₂ = 31.9988 gm/mole then 616 gm of O₂ = 616 / 31.9988 = 19.25 mole

According to reaction 1 mole of O₂ produce 2 mole of water then 19.25 mole of O₂ produce 19.25 $\times$ 2 / 1 = 38.50 mole of water

to calculate volume of water vapour use ideal gas equation

We know that PV = nRT

V = nRT/P

n = 38.50 mole,

T = 308⁰C = 308+273.15 = 581.15K,

P= 0.952 atm,

R = 0.08205 L atm mol^-1 K^-1 ( R = gas constant)

V = ?

Substitute these value in above equation.

V = 38.50 $\times$ 0.08205 $\times$ 581.15 / 0.952 = 1928.37 L

1928.37 L water vapour produced