Question

Mole fraction of urea in an aqueous solution containing 10%urea by mass of solution is ......
a)0.032
b)0.968
c)0.90
d)0.10

Answer 1

Mole fraction of urea is 0.032

Explanation:

Mole fraction of a substance is the ratio of the moles of that substance to the total number of moles present.

Given : 10 g of urea is present in 100 g of solution. Thus mass of wtaer = (100-10) g = 90 g.

${\text {mole fraction of urea}}=\frac{\text{moles of urea}}{\text {moles of urea + moles of water}}$

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}$

Thus ${\text{moles of urea}}=\frac{10g}{60g/mol}=0.17mol$

${\text{moles of water}}=\frac{90g}{18g/mol}=5mol$

${\text {mole fraction of urea}=\frac{0.17}{0.17+5}=0.032$

The mole fraction of urea is 0.032

Learn more about mole fraction

https://brainly.com/question/3383567

https://brainly.com/question/12154684

Answer 2

Mole fraction of urea is 0.032.