Answer: The number of moles of hydrogen gas generated is [tex]2.33\times 10^{-3}mol[/tex]
Explanation:
To calculate the number of moles of hydrogen gas, we use the equation given by ideal gas which follows:
[tex]PV=nRT[/tex]
where,
P = pressure of the gas = 0.781 atm
V = Volume of the gas = 71.85 mL = 0.07185 L (Conversion factor: 1 L = 1000 mL)
T = Temperature of the gas = [tex]20^oC=[20+273]K=293K[/tex]
R = Gas constant = [tex]0.0821\text{ L. atm }mol^{-1}K^{-1}[/tex]
n = number of moles of hydrogen gas = ?
Putting values in above equation, we get:
[tex]0.781atm\times 0.07185L=n\times 0.0821\text{ L.atm }mol^{-1}K^{-1}\times 293K\\\\n=\frac{0.781\times 0.07185}{0.0821\times 293}=2.33\times 10^{-3}mol[/tex]
Hence, the number of moles of hydrogen gas generated is [tex]2.33\times 10^{-3}mol[/tex]
