You Are Dissolving a Gas in Water

You are dissolving a gas in water. If the partial pressure of the gas is 1 atm, and the concentration is .5g per 50mL of solution, then what is the concentration of gas at 800mmHg? How many grams of gas are dissolved in the water now?

A) 0.66g dissolved at a concentration of 0.013 g/mL
B) 0.66 g dissolved at a concentration of 0.02 g/mL
C) 0.5 g dissolved at a concentration of 0.013 g/mL
D) 0) 5 g dissolved at a concentration of 0.02 g/mL
E) 1.0 g dissolved at a concentration of 0.02 g/mL