In which of the nitrogen fertilizers the mass fraction of the nutrient nitrogen is the highest:

In which of the nitrogen fertilizers the mass fraction of the nutrient nitrogen is the highest: a) ammonium chloride NH4Cl; b) ammonium sulfate (NH4) 2SO4; c) urea (NH2) 2СО?

Given: Solution:
a) NH4Cl 1) Find the relative small mass of substances.
b) (NH4) 2SO4 a) Mr (NH4Cl) = 14 + 1 * 4 + 35.5 == 53.5
c) (NH2) 2CO b) Mr ((NH4) 2SO4) = 14 * 2 + 1 * 8 + 32 + 16 * 4 = 28 + 8 + 32 + 64 = 132
c) Mr ((NH2) 2CO) = 14 * 2 + 1 * 4 + 12 + 16 = 60
a) w (N) -? 2) Find w (N) in each substance.
b) w (N) -? a) w (N) = 14 * 1 / 53.5 = 0.2616 or 26.16%
c) w (N) -? b) w (N) = 14 * 2/132 = 0.2121 or 21.21%
c) w (N) = 14 * 2/60 = 0.4667 or 46.67%
Answer: In urea, the mass fraction of the nutrient nitrogen is greater.