Calculate the root mean square speed of hydrogen molecule at STP

Explanation

`c = sqrt((3PV)/(M))`
`P = 1 atm = 101.3 k Pa`
`V = 22.4 dm^(3)`
`M = 2 g mol^(-1) = 0.002 kg mol^(-1)`
Substituting the values,
`c = sqrt((3 xx 101.3 xx 22.4)/(0.002)) = 1844.91 ms^(-1)`
Alternative method:
`c = sqrt((3RT)/(M))`
`R = 8.314 k Pa dm^(3) K^(-1) mol^(-1), T = 273 K`,
`M = 0.002 kg mol^(-1)`
Substituting the values,
`c = sqrt((3 xx 8.314 xx 273)/(0.002) = 1845.15 ms^(-1)`