Q.

A soft drink was bottled with partial pressure of CO2 of 6 bar over the liquid at room temperature. The partial pressure of CO2 over the solution approaches a value of 60 bar when 88 g of CO2 is dissolved in 1 kg of water at room temperature. The approximate pH of the soft drink is _________ ×10-1.

(first dissociation constant of H2CO3=4.0×10-7, log 2=0.3

density of the soft drink =1 g ml-1)


Ans.

(36)

P1P2=m1m2=660=m188

m1=8.8g    Mole=8.844=0.2

pH=12pKa-logc=12×6.4-log(2×10-1)

Ka=4×10-7    pKa=7-0.6=6.4⇒3.2+0.35=3.55=35.5×10-1=36×10-1