Question

What is the mass of nitrogen in 1000 kg of urea [CO(NH2)2].
[C = 12] (Answer to the nearest kg.)

August 4, 2024

Answer

Molecular weight of urea [CO(NH₂)₂]

= 12 + 16 + 2[14 + 2(1)]

= 12 + 16 + 2[16]

= 28 + 32

= 60 g

Converting the given weight of urea in grams,

1000 kg of urea = 1000 × 10³ g of urea

60 g of urea contains 28 g of nitrogen

∴ 1000 × 10³ g of urea will contain = $28\over 60$ × 1000 × 1000

= 466.66 x 10³ g ≈ 467 × 10³ g

= 467 kg of nitrogen.

Hence, mass of nitrogen is 467 kg

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