Question

Calculate the vapour pressure of a solvent above a solution containing 83.99g of solute x(molecular weight 195.62) per 1200g of h20 at 20°c.the vapour pressure of h2O at 20°c is 17.53mmhg

Answer 1

p_H2O=p_H2O^**x_H2O (Raoult's law)

n_H2O=1200/18 = 66.667 mol

n_x = 83.99/195.62 = 0.429

x_H2O = 66.667/(66.667+0.429) = 0.99361

p_H2O=17.53*0.99361 = 17.42 mmhg