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MODEL PAPER 2025 — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 20253 Marks
Question
$a.$ Write down the reaction occurring on two inert electrodes when electrolysis of copper chloride is done. What will happen if a concentrated solution of copper sulphate is replaced with copper chloride?
$b.$ Write an expression for the molar conductivity of aluminium sulphate at infinite dilution according to Kohlrausch law.
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Answer

$a)$ Product of electrolysis of Copper Chloride
Cathode$(-)$
$Cu^{2+} + 2e \leftarrow Cu(s)$
anode$(+)$
$2CI \rightarrow Cl_2+ 2e$
Product of electrolysis of concentrated Copper Sulphate
Anode$(+) SO_4^2S_2O_8 + 2e$
Cathode $(-) Cu^{2+} + 2e \leftarrow Cu(s)$
$(B) \Lambda^0{ }_{\mathrm{m}}\left[\mathrm{Al}_2\left(\mathrm{SO}_4\right)_3\right]=2 \lambda^0{ }_{\mathrm{m}}\left(\mathrm{Al}^{3+}\right)+3 \lambda^0{ }_{\mathrm{m}}\left(\mathrm{SO}_4{ }^{2-}\right)$

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