Determine the quantity (g) of pure CaCl2 in 7.5 g of CaCl2•9H2O

3. 049g

Explanation:

Molar mass of Ca = 40

Molar mass of Cl = 35.5

H = 1, O = 16

Molar mass of CaCl2.9H20 = [40 + (35.5*2) + (9*18) ]

CaCl2.9H20 = 273g/mol

Molar mass of CaCl2 = 40 + (35.5*2) = 111g/mol

111g of CaCl2 is present in 273g of CaCl2.9H20

Xg of CaCl2 is present in 7.5g of CaCl2.9H20

X = (7.5*111) / 273

X = 3.049g