Electrolytes and their dissociation
Answers are for parents and teachers.
1
Write dissociation equations for K₃PO₄, Mg(NO₃)₂ and H₃PO₄ (step 1).
K₃PO₄ → 3K⁺ + PO₄³⁻; Mg(NO₃)₂ → Mg²⁺ + 2NO₃⁻; H₃PO₄ → H⁺ + H₂PO₄⁻.
2
How many moles of Fe³⁺ ions are in a solution of 5 mol Fe₂(SO₄)₃?
10
3
Why does distilled water hardly conduct current?
It contains very few free ions; water molecules hardly dissociate.
4
Write the dissociation of NaHSO₄ in two steps.
NaHSO₄ → Na⁺ + HSO₄⁻; HSO₄⁻ → H⁺ + SO₄²⁻.
5
How does a magnesium atom (Mg) differ from a magnesium ion (Mg²⁺)?
The ion has lost two electrons: Mg²⁺ has 10 electrons, charge +2 and a stable 8-electron outer shell; the atom is neutral, has 12 electrons and is a strong reducing agent.