CBSE 2025 · Region 6 · Set 1 · Q24 · 3 marks
Give reasons for the following:(a)The pH of aqueous NaCl increases when it is electrolysed.(b)Unlike dry cell, mercury cell has a constant cell potential through its lifetime.(c)Conductivity of solution decreases with dilution.
Give reasons for the following:
(a)
The pH of aqueous NaCl increases when it is electrolysed.
(b)
Unlike dry cell, mercury cell has a constant cell potential through its lifetime.
(c)
Conductivity of solution decreases with dilution.
Marking-scheme solution
(a)
Because of the formation of NaOH / Due to the formation of OH⁻ ions.
(b)
Because the overall reaction does not involve any ion in solution whose concentration can change during its life time.
(c)
Because the number of ions per unit volume that carry current in a solution decreases.
ElectrochemistryElectrolytic Cells and ElectrolysisUnderstandshort_answermedium
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CBSE Class 12 Chemistry past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.