Question

Ammonia NH3 with Kb = 1.8 x 10^05 is added to 100 mL ofwaterat room temperature and the vapor pressure of water abovethesoultion drops to P = 0.03 atm. What is the pH of the solutioninthe limit that any gas phase NH3 is negliglble.

a) Calculate the vapor pressure above room temperaturewaterwhere delta H vapor = 40.7 kj/mol

I got .815 atm not sure if it's right

b) Calculate the mole fraction of the solvent from Raoult'slawfrom part a.

c) Calculate the total number of moles of the solute fromthesolvent mole fraction.

d) What is the total solute concentration assuming aconstant100 mL volume?

e) Assuming that the concentration determined in thepreviousstep corresponds to the inital amount of added NH3 (aq),what isthe pH of the solution?