Question

Question #ad42b

Answer 1

Volume of oxygen at STP present in 2L air is `=2Lxx21%=0.42L`

Number of moles of `O_2` present in `0.42L` oxygen at STP will be

`="volume of oxygen"/"molar volume of the gas"`

`=(0.42L)/(22.4L/"mol")=18.75xx10^-3mol`