A solution is prepared by dissolving 2.0 g of glucose and 4.0 g urea in 100 g of water at 298 K . Calculate the vapour pressure of the solution ,If the vapour pressure of pure water is23.756 torr. (Molecular mass of urea = 60 and glucose= 180g mol^(-1))

A solution is prepared by dissolving 2.0 g of glucose and 4.0 g urea i

1.	A solution is prepared by dissolving 2.0 g of glucose and 4.0 g urea in 100 g of water at 298 K . Calculate the vapour pressure of the solution ,If the vapour pressure of pure water is23.756 torr. (Molecular mass of urea = 60 and glucose= 180g mol^(-1))
Answer» <P> SOLUTION :(i)`x_A =( n_A)/( n_A+n_B)` ` n_A ="No of moles WATER "` `n_B = "No. of MOLESOF glucose " ` `n_A =( 100)/( 18 ) = 5.555` ` n_B =(2)/( 180) = 0.0111` Total moles ` (n_A+n_B) = 5.566` (ii)Urea ` n_A = "No. of moles of water " ` ` n_B=" No. of mole of urea " ` `n_A = 5.555` ` n_B=( 4)/( 60) = 0.0666 " moles of urea "` Total moles ` = 0.555+ 0.066 moles ` `x_B = ( n_A)/( n_A+n_B) ` `= ( 5.555)/( 5.621) = 0.9882` `P_B = P^(@) xx x_B ` `""= 23.756xx 0.9882` ` P_B = 23.42 torr`