Question

lewis and stroch measured the partial pressure of br2 above its solution in ccl4. determine the henry's law constant ( on mole fraction scale) for br2 in ccl4 from the data given below

solution mole fraction of br2 vapour pressure of br2

0.00394 1.52

0.00420 1.60

0.00599 2.39

0.0102 4.27

0.0130 5.43

0.0236 9.57

0.0238 9.83

0.0250 10.27

Answer 1

According to henry’s law,the amount (concentration ) of dissolved gas is proportional to the partial pressure of the gas in the vapour phase

Or, H=Ca/p ,

Where H=henry’constant for the gas

Ca=concentration of gas in aqueous phase

P= partial pressure of the gas in the vapour phase

solution mole fraction of br2 vapour pressure of br2   (atm)                 (H)=ca/p

0.00394 1.52                                                   0.00259

0.00420 1.60                                                   0.00262

0.00599 2.39                                                    0.00251

0.0102 4.27                                                    0.00239

0.0130 5.43                                                 0.00239

0.0236 9.57                                                    0.00247

0.0238 9.83                                                    0.00242

0.0250 10.27                                                0.00243

                                                                                             Average H=0.00248 atm^-1