Strong and weak electrolytes
Answers are for parents and teachers.
1
How many ions form if 1 formula unit of Fe₂(SO₄)₃ and 2 formula units of K₂CO₃ dissociate completely?
11
2
Assess H₂SeO₄, HIO and HMnO₄ by the m – n rule.
H₂SeO₄: 4 – 2 = 2 strong; HIO: 1 – 1 = 0 weak; HMnO₄: 4 – 1 = 3 strong.
3
Write the dissociation equations of Ba(OH)₂ and H₂SO₄.
Ba(OH)₂ → Ba²⁺ + 2OH⁻; H₂SO₄ → 2H⁺ + SO₄²⁻.
4
Why does a 0.1 M HCl solution conduct better than a 0.1 M CH₃COOH solution?
HCl dissociates almost completely, CH₃COOH only slightly, so it has far fewer ions.
5
Why should only the teacher work with a conductivity apparatus?
The apparatus is connected to mains voltage, and wet hands and solutions create a risk of electric shock.