Answer: There are 1.78 moles in 40.0 L of He gas at STP
Explanation:
According to ideal gas equation:
[tex]PV=nRT[/tex]
P = pressure of gas = 1 atm (STP)
V = Volume of gas = 40.0 L
n = number of moles = ?
R = gas constant =[tex]0.0821Latm/Kmol[/tex]
T =temperature =[tex]273K[/tex] (STP)
[tex]n=\frac{PV}{RT}[/tex]
[tex]n=\frac{1atm\times 40.0L}{0.0821Latm/K mol\times 273K}=1.78moles[/tex]
Thus there are 1.78 moles in 40.0 L of He gas at STP
