JEE MAIN - Chemistry (2020 - 9th January Morning Slot - No. 14)
The hardness of a water sample containing
10–3 M MgSO4 expressed as CaCO3 equivalents
(in ppm) is ______.
(molar mass of MgSO4 is 120.37 g/mol)
(molar mass of MgSO4 is 120.37 g/mol)
Answer
100
Explanation
Equivalance of MgSO4 = Equivalance of CaCO3
$$ \Rightarrow $$ 10-3 $$ \times $$ 2 = [CaCO3] $$ \times $$ 2
$$ \Rightarrow $$ [CaCO3] = 10-3 M = 10-3 mol/lit
= 10-3 $$ \times $$ 100 g/lit
= 100 mg/lit
= 100 ppm
$$ \Rightarrow $$ 10-3 $$ \times $$ 2 = [CaCO3] $$ \times $$ 2
$$ \Rightarrow $$ [CaCO3] = 10-3 M = 10-3 mol/lit
= 10-3 $$ \times $$ 100 g/lit
= 100 mg/lit
= 100 ppm
Comments (0)
