A 0.194-g sample of a nonvolatile solid solute dissolves in 9.82 g of cyclohexane. The change in the freezing point of the solution is 2.94°C. (Kf of Cyclohexane is 20.0°C/m) a. What is the molality of the solute in the solution?
b. Calculate the molar mass of the solute to the correct number of significant figures.
c. The same mass of solute is dissolved in 9.82 g of TBA instead of cyclohexane. (Kf of TBA is 9.1°C/m) What is the expected freezing point?

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.

the solar system used to have much dust particles option no d

c) should be the answer.