The boiling point of water at 735mmHg is 99.073C. What mass of NaCl should be added to 3.11kg water to increase the boiling point to 100.000C. Kb for water = 0.510K kg mol-1.

Answer 1

delta T = Kb*molality
Solve for molality.

m = moles/kg solvent.
Solve for moles.

moles = grams/molar mass
Solve for grams.

Answer 2

g BaCl2 = 1.38moles BaCl2 x molar mass BaCl2 (which is 208.23)
=287.3574g