4 liters of water are equilibrated with a gas mixture containing carbon dioxide at a partial pressure of 0.3 atm. Henry's law constant for H2CO3 solubility is 2.0g/L*atm. How many grams of CO2 are dissolved in the water and pH of this water (neglect secondary dissociation of carbonic acid)?
If H2CO3 dissolves without dissociating, achieving equilibrium with the atmosphere, then solution is closed to atmosphere. H2CO3 then dissociates. Find the pH of this solution and compare it to the above. 

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