Chemistry
Urea (CO(NH2)2) is an important nitrogenous fertilizer. Urea is sold in 50 kg sacks. What mass of nitrogen is in one sack of urea?
Mole Concept
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Answer
Molar mass of urea [CO(NH2)2] = 12 + 16 + 2[14 + (2 x 1)]
= 28 + 2(16)
= 28 + 32
= 60 g
50 kg of urea = 50,000 g of urea
Nitrogen in 60 g of CO(NH2)2 = 2 x 14 = 28 g
∴ Nitrogen in 50,000 g urea =
= 23,333 g = 23.3 kg
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