Answer:
[HCl] : 12.3 M ; [HCl] : 16.7 m; [HCl] in mole fraction = 0.23
[HNO₃]: 15.7 M; [HNO₃]: 30 m ; [HNO₃] in mole fraction = 0.39
[H₂SO₄]: 17.8 M ; [H₂SO₄]: 193.8 m ; [H₂SO₄] in mole fraction = 0.78
[CH₃COOH]: 17.3 M ; [CH₃COOH]: 1650 m ; [CH₃COOH] in mole fraction: 0.96
[NH₃]: 14.7 M ; [NH₃]: 22.7 m ; [NH₃] in mole fraction = 0.29
Explanation:
Percent by mass means X g of solute contained in 100 g of solution
Mass of solvent: 100 g - X % by mass
Solution density = Solution mass / Solution volume
Solution Volume = Solution mass / Solution density
Molality = mol of solute / kg of solvent
Molarity = mol of solute / L of solution
Mole fraction = Moles of solute / Total moles
Total moles = moles of solute + moles of solvent
Mass of solvent: 100 g - 38 g = 62 g
Moles of solvent → 62 g . 1 mol/ 18g = 3.44 moles
Mass of solute → 38 g ; Moles of solute → 38 g . 1mol/36.45 g = 1.04 moles
Total moles = 3.44 mol + 1.04 mol = 4.48 moles
Mole fraction = 1.04 / 4.48 = 0.23
Mass of solvent → from g to kg → 62 g . 1kg/1000g = 0.062kg
Molality → 1.04 mol / 0.062 kg = 16.7 mol/kg → 16.7 m
Solution volume = 100 g / 1.19 g/mL → 84.03 mL
Solution volume → from mL to L → 84.03 mL . 1L/ 1000mL = 0.0840L
Molarity → 1.04 mol / 0.0840L = 12.3 M
HNO₃ → 1.42 g/mL; 70%
Mass of solvent: 100 g - 70 g = 30 g
Moles of solvent → 30 g . 1 mol/ 18g = 1.67 moles
Mass of solute → 70 g ; Moles of solute → 70 g . 1mol/ 63 g = 1.11 moles
Total moles = 1.67 mol + 1.11 mol = 2.78 moles
Mole fraction = 1.11 / 2.78 = 0.39
Mass of solvent → from g to kg → 30 g . 1kg/1000g = 0.030kg
Molality → 1.11 mol / 0.030 kg → 30 m
Solution volume = 100 g / 1.42 g/mL → 70.4mL
Solution volume → from mL to L → 70.4 mL . 1L/ 1000mL = 0.0704L
Molarity → 1.11 mol / 0.0704L = 15.7 M
Mass of solvent: 100 g - 95 g = 5 g
Moles of solvent → 5 g . 1 mol/ 18g = 0.277 moles
Mass of solute → 95 g ; Moles of solute → 95 g . 1 mol/ 98 g = 0.969 moles
Total moles = 0.277 mol + 0.969 mol = 1.246 moles
Mole fraction = 0.969 / 1.246 = 0.78
Mass of solvent → from g to kg → 5 g . 1kg/1000g = 0.005 kg
Molality → 0.969 mol / 0.005 kg → 193.8 m
Solution volume = 100 g / 1.84 g/mL → 54.3 mL
Solution volume → from mL to L → 54.3 mL . 1L/ 1000mL = 0.0543 L
Molarity → 0.969 mol / 0.0543L = 17.8 M
- CH₃COOH → 1.05 g/mL; 99 %
Mass of solvent: 100 g - 99 g = 1 g
Moles of solvent → 1 g . 1 mol/ 18g = 0.055 moles
Mass of solute → 99 g; Moles of solute → 99 g . 1 mol/ 60 g = 1.65 moles
Total moles = 0.055 mol + 1.65 mol = 1.705 moles
Mole fraction = 1.65 / 1.705 = 0.96
Mass of solvent → from g to kg → 1 g . 1kg/1000 g = 0.001 kg
Molality → 1.65 mol / 0.001 kg → 1650 m
Solution volume = 100 g / 1.05 g/mL → 95.2mL
Solution volume → from mL to L → 95.2 mL . 1L/ 1000mL = 0.0952L
Molarity → 1.65 mol / 0.0952 L = 17.3 M
Mass of solvent: 100 g - 28 g = 72 g
Moles of solvent → 72 g . 1 mol/ 18g = 4 moles
Mass of solute → 28 g; Moles of solute → 28 g . 1mol/ 17 g = 1.64 moles
Total moles = 4 mol + 1.64 mol = 5.64 moles
Mole fraction = 1.64 / 5.64 = 0.29
Mass of solvent → from g to kg → 72 g . 1kg/1000g = 0.072kg
Molality → 1.64 mol / 0.072 kg → 22.7 m
Solution volume = 100 g / 0.90 g/mL → 111.1mL
Solution volume → from mL to L → 111.1 mL . 1L/ 1000mL = 0.111L
Molarity → 1.64 mol / 0.111L = 14.7 M