Answer :
The number of moles of water vapor formed in the reaction is 0.158 moles
What is the ideal gas equation?
The ideal gas equation shows the relationship between number of moles, temperature, volume and pressure.
Now;
P = 122.3 kilopascals or 1.21 atm
V = 5.4 L
T = 730°c or 1003 K
n = ?
R = 0.082 atmLK-1mol-1
PV = nRT
n = PV/RT
n = 1.21 * 5.4/0.082 * 1003
n = 6.53/82.2
n = 0.079 moles
The equation of the reaction is; O2 (g) + 2H2(g) ---->2H2O(g)
If 1 mole of O2 formed 2 moles of H2O
0.079 moles of O2 yield x moles of H2O
x = 0.079 * 2/1
= 0.158 moles
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