Answer : The correct option is, (A) 51.1%
Explanation :
Mass percent : It is defined as the mass of the given component present in the total mass of the compound.
Formula used :
[tex]\text{Mass} \%H_2O=\frac{\text{Mass of }H_2O}{\text{Mass of }MgSO_4.7H_2O}\times 100[/tex]
First we have to calculate the mass of [tex]H_2O[/tex] and [tex]MgSO_4.7H_2O[/tex].
Mass of [tex]H_2O[/tex] = 18 g/mole
Mass of [tex]7H_2O[/tex] = 7 × 18 g/mole = 126 g/mole
Mass of [tex]MgSO_4.7H_2O[/tex] = 246.47 g/mole
Now put all the given values in the above formula, we get the mass percent of [tex]H_2O[/tex] in [tex]MgSO_4.7H_2O[/tex].
[tex]\text{Mass} \%H_2O=\frac{126g/mole}{246.47g/mole}\times 100=51.1[/tex]
Therefore, the mass percent of [tex]H_2O[/tex] in [tex]MgSO_4.7H_2O[/tex] is, 51.1%
