Chemistry
AB2 is a hard crystalline solid having high melting and boiling points. It conducts electricity in aqueous and molten states.
(i) AB2 conducts electricity due to the presence of free …………… (ions/molecules/electrons).
(ii) During electrolysis of AB2 in aqueous state, it is observed that cathode becomes thick and anode thin. The anode material will be …………… (graphite/metal A).
Answer
(i) AB2 conducts electricity due to the presence of free ions.
Reason — In the solid state, ions are locked in a crystal lattice. Once melted (molten) or dissolved in water (aqueous), the lattice breaks down, allowing the ions to move freely and carry an electric charge.
(ii) During electrolysis of AB2 in aqueous state, it is observed that cathode becomes thick and anode thin. The anode material will be metal A.
Reason — Cathode becomes thick → metal is deposited there (reduction).
Anode becomes thin → metal dissolves into solution (oxidation).
This happens only if the anode itself is made of the same metal (A), which supplies ions to the solution.
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