On recrystallization 20g of magnesium tetraoxosulphate(vi) crystal NgSo4•YH2O, the value of y is _______(Ng=24,S=32,O=16,H=1)

1 answer

To find the value of y, we need to first calculate the molar mass of MgSO4•YH2O.

Molar mass of MgSO4 = 24 (Mg) + 32 (S) + (4 x 16) = 24 + 32 + 64 = 120 g/mol

Molar mass of H2O = 2(1) + 16 = 18 g/mol

Therefore, the molar mass of MgSO4•YH2O is 120 + 18y g/mol.

Given that 20g of MgSO4•YH2O was recrystallized, we can set up the following equation and solve for y:

20 = (120 + 18y)/molar mass of MgSO4•YH2O

20 = (120 + 18y)/(120 + 18y)

20(120 + 18y) = 120 + 18y

2400 + 360y = 120 + 18y

360y - 18y = 120 - 2400

342y = 2280

y = 2280/342

y = 6.67

Therefore, the value of y rounded to the nearest whole number is 7.