Question

Calculate the concentration (in percentage by weight) of a solution obtained by mixing $300g25\%$ by weight solution of $N{H}_{4}Cl$ and $150gof40\%$ by weight solution of $N{H}_{4}Cl$ .

Answer 1

Answer: 30

Weight of solution $IandII=300+150=450g$

Weight of $N{H}_{4}Cl$ in $Isolution=\frac{25\times 300}{100}=75g$

Weight of $N{H}_{4}Cl$ in $IIsolution$ $=\frac{40\times 150}{100}=$ $60g$

$\therefore$ Total weight of $N{H}_{4}Cl=75+60=135g$

$\therefore \%bywt.ofmixedsolution=\frac{135}{450}\times 100=30\%$