Oxygen gas generated by the decomposition of potassium chlorate is collected. The volume of oxygen collected at `24^(@)C` and atmospheric pressure of `760 m m Hg` is `128 mL`. Calculate the mass `(` in grams `)` of oxygen gas obtained. The pressure of water vapour at `24^(@)C` is `22.4 m m Hg`.

Options

A. `1.36`
B. `1.52g`
C. `0.163g`
D. `1.63g`

Answer

C

Explanation

From the total pressure and the vapour pressure of water we can calculate the partial pressure of `O_(2)`.
`P_(O_(2))=P_(tau)-P_(H_(2)O)`
`=660-22.4`
`=737.6mm Hg`
From the ideal gas equation we write.
`m=(PVM)/(RT) =((0.974atm)(0.128L)(32.0g//mol))/((0.0821Latm//Kmol)(273+24)K)=0.163g.`