Question

28. to make For which of the following compounds is it possible a 1.0M solution at 20°C? (a) Cusly, solubility = 32,0g/100 ml (6) Balolt), solubility = 3.9g/100 mL (6) FeCl2, solubility = 68.5g/100 ml (d) Ca(OH)2, solubility = 0.173 g/100 ml

Answer 1

To prepare 1.0 M solution of any solute, is 1.0 mole of solute per liter of solution.

a. CuSO₄ mol wt= 159.60 g/mol, to make 1.0 M CuSO₄ solution, dissolve 159.6 g per 1000mL of solution. Its solubility is 32 g/100mL that is 320 g/1000 mL of solution. Hence 1.0 M solution of CuSO₄ can de prepared.

b. Ba(OH)₂ mol wt= 171.34 g/mol, to make 1.0 M Ba(OH)₂ solution, dissolve 171.34 g per 1000 mL of solution. But solubility of Ba(OH)₂ is only 3.9 g/100 mL that is 39.0 g/1000 mL of solution. Hene 1.0 M solution of Ba(OH)₂ is not posible.

c. FeCl₂ mol wt= 126.75 g/mol, to make 1.0 M FeCl₂ solution, dissolve 126.75 g per 1000 mL of solution. Its olubility of FeCl₂ is 68.5 g/100 mL i.e. 685 g/1000 mL of solution. Hene 1.0 M solution of FeCl₂ is posible.

d. Ca(OH)₂ mol wt= 74.09 g/mol, to make 1.0 M Ca(OH)₂ solution, dissolve 74.09 g per 1000 mL of solution. But solubility of Ca(OH)₂ is only 0.173 g/100 mL that is 1.73 g/1000 mL of solution. Hene 1.0 M solution of Ca(OH)₂ is not posible.