A 500mL Soda water is packed under 2.5 atm and CO2 pressure at 298 K. Find out the quantity of CO2 present in the bottle if Henry�s law constant for CO2 in water is 1.67x108 Pa at 298 K.

Given: KH= 1.67×108 Pa Pressure of CO2= 2.5atm 1 atm= 1.01235 x 105 Pa So Pressure of CO2 = 2.5 x 1.01235 x 105Pa = 2.533125 x 105Pa According to Henry’s law p = KH x X X= p / KH = 2.533125 x 105Pa / 1.67×108 Pa X = 1.52 x 10 -3 Given that the bottle contains 500mL of soda water Volume of water = 500mL Density of water = 1 g/mL Mass = Volume X Density Mass = 500 x 1 = 500 Molar mass of water is 18g / mol Number of moles of water = Mass/(Molar mass) = 500/18 = 27.78 moles of water We know that mole fraction X = nCO2/(nCO2+n H2O) Value of mole fraction is negligible as compared to 1 Hence X = nCO2/(n H2O) 1.52 x 10 -3 = n CO2 / 27.78 n CO2 = 0.042 mol Molar mass of CO2 = 44 g / mol Mass = molar mass x Number of moles = 0.042 X 44 = 1.848g Hence, quantity of CO2 present in the bottle is 1.848 g

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