Question

At $760torr$ pressure and ${20}^{\circ }C$ temperature, $1L$ of water dissolves $0.04gm$ of pure oxygen or $0.02gm$ of pure nitrogen. Assuming that dry air is composed of $20$% oxygen and $80$% nitrogen (by volume). The masses (in g/L) of oxygen and nitrogen dissolved by $1L$ of water at ${20}^{\circ }C$ exposed to air at a total pressure of $760torr$ are respectively.

• A. $0.008,0.016$
• B. $0.016,0.008$
• C. $0.16,0.08$
• D. $0.04,0.02$

Answer 1

The correct option is A $0.008,0.016$

Mass of Oxygen = $\frac{20}{100}\times 0.04=0.008g/L$

Mass of Nitrogen = $\frac{80}{100}\times 0.02=0.0016g/L$

Hence the correct option is [A]