Question

6g of ura is desolved in 90grames of water the mole fraction of solute is

Answer 1

▶ Solution :

✴ Given :

Weight of urea = 6g

Weight of water = 90g

✴ To Find :

Mole fraction of solute.

✴ Formula :

▪ Mole fraction of solute is defined as ratio of moles of solute to the moles of solution.

Mathematically,

$\boxed{\bf{\pink{X_{solute}=\dfrac{n_{solute}}{n_{solution}}}}}$

▪ Molecular weight of urea = 60g/mol

▪ Molecular weight of water = 18g/mol

▪ Solute = urea

▪ Solvent = water

✴ Calculation :

$\implies\sf\:moles\:of\:urea=\dfrac{6}{60}=0.1\\ \\ \implies\sf\:moles\:of\:water=\dfrac{90}{18}=5\\ \\ \mapsto\sf\:X_{urea}=\dfrac{n_{urea}}{n_{urea}+n_{water}}\\ \\ \mapsto\sf\:X_{urea}=\dfrac{0.1}{0.1+5}\\ \\ \mapsto\boxed{\bf{\purple{X_{urea}=0.0196}}}$