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Question
22.22 gram of urea was dissolved in 300 grams of water. Calculate the number of moles of urea and molality of the urea solution.
(Given: Molar mass of urea = 60 gram mol−1)
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Solution
Given: Molar mass of urea = 60 gram mol−1
Moles of urea = `22.22/60`
= 0.370 moles
Formula: Molality (m) = `"Moles of urea"/"Mass of water" xx 1000`
= `(0.370 xx 1000)/300`
= 1.23 moles kg−1
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