Calculate amount of Nitrogen in one bag (50 kg) of Urea.

Molecular formula of Urea is CON₂H₄

Relative molecular mass of CON₂H₄
   = 12 + 16 + 2 x 14 + 4 x 1
   = 12 + 16 + 28 + 4
   = 60 amu

Wt. of N in CON₂H₄ = 28 g

% of N = $\dfrac{\text{Wt. of N}}{\text{Total Wt. of CON}$2\text{H}4}\times 100

= $\dfrac{28}{60}$ x 100 = 46.67%

Wt. of N in 50 kg CON₂H₄

= $\dfrac{46.67}{100}$ x 50 = 23.33 kg

∴ Amount of Nitrogen in one bag (50 kg) of Urea is 23.33 kg.