Chemistry - Mole Concept Question with Solution | TestHub

Mass of Phosphorus$=31\text{u}$
Since 1 mole of${\text{Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_{\text{7}}$has$\mathrm{2 }\text{g\hspace{0.17em}}$atoms of P
Mass of Phosphorus in${\text{Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_7=62\text{u}$
Mass of${\text{Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_{\text{7}}=222.5\text{u}$
Weight of${\text{Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_{\text{7}}=2.6\text{\hspace{0.17em}g\hspace{0.17em}}$
Weight of organic compound$=1.6\text{\hspace{0.17em}g}$
$\text{Percentage\hspace{0.17em}of\hspace{0.17em}phsphorus}=\frac{\text{Mass of phsphorus }}{{\text{Mass of Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_{\text{7}}}\times \frac{{\text{Weight of Mg}}_{\text{2}}{\text{P}}_{\text{2}}{\text{O}}_{\text{7 }}}{\text{Weight of organic compound}}\times 100$
$\text{Percentage\hspace{0.17em}of\hspace{0.17em}phsphorus}=\frac{62}{222.5}\times \frac{2.6}{1.6}\times 100=45.38\%$