A water sample contains 22.2 mg of CaCl 2 in 1 L of sample. The degree of hardness of water in terms of CaCO 3 equivalent is ppm. [Molar mass of CaCO 3=100 g mol -1, molar mass of CaCl 2=111 g mol -1 ]

Question

A water sample contains 22.2 mg of CaCl 2 in 1 L of sample. The degree of hardness of water in terms of CaCO 3 equivalent is ppm. [Molar mass of CaCO 3=100 g mol -1, molar mass of CaCl 2=111 g mol -1 ] (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

ppm is parts per million (106). This is equivalent to mg per litre. 1 L of water contains 22.2 mg of CaCl 2. Now, 111 g of CaCl 2 ≡ 100 g CaCO 3 22.2 mg of CaCl 2=(22.2 × 100/111) =20 mg of CaCO 3 in 1 L of water ∴ Hardness of water sample =20 ppm

Q. A water sample contains 22.2mg of CaCl2​ in 1L of sample. The degree of hardness of water in terms of CaCO3​ equivalent is ____ppm. [Molar mass of CaCO3​=100gmol−1, molar mass of CaCl2​=111gmol−1 ]

ppm is parts per million (106). This is equivalent to mg per litre. 1L of water contains 22.2mg of CaCl2​. Now, 111g of CaCl2​≡100gCaCO3​ 22.2mg of CaCl2​=11122.2×100​ =20mg of CaCO3​ in 1L of water ∴ Hardness of water sample =20ppm

Q. $A$ water sample contains $22.2 m g$ of $C a C l_{2}$ in $1 L$ of sample. The degree of hardness of water in terms of $C a C O_{3}$ equivalent is ____ $pp m$ .
[Molar mass of $C a C O_{3} = 100 g m o l^{- 1}$ , molar mass of $C a C l_{2} = 111 g m o l^{- 1}$ ]