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Question
Calculate the mass of nitrogen supplied to soil by 5 kg of urea [CO(NH2)2].
[O = 16; N = 14; C = 12; H = 1]
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Solution
Molecular mass of Urea [CO(NH2)2] = [12 + 16 + (14 + 2 × 1) × 2]
= [12 + 16 + 32] = 60
Weight of nitrogen in 60 kg = 28 kg
∴ Weight of nitrogen in 5 kg = `28/60 xx 5`
= 2.33 kg
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