KCET 2025 Chemistry Paper

To determine the quantity of electricity required to deposit various metals at the cathode, we use Faraday's laws of electrolysis, where 1 Faraday (F) is equivalent to 96500 coulombs (C) per mole of electrons. Let's analyze each metal ion:
Silver (Ag+):
Reaction: Ag++e−⟶Ag
Calculation: 1×96500C=96500Cmol−1
Requires 1 Faraday per mole.
Magnesium (Mg2+) :
Reaction: Mg2++2e−⟶Mg
Calculation: 2×96500C=193000Cmol−1
Requires 2 Faradays per mole.
Aluminum (Al3+) :
Reaction: Al3++3e−⟶Al
Calculation: 3×96500C=289500Cmol−1
Requires 3 Faradays per mole.
Titanium (Ti4+) :
Reaction: Ti4++4e−⟶Ti
Calculation: 4×96500C=386000Cmol−1
Requires 4 Faradays per mole.
The correct matches for the amounts of electricity required to deposit each metal are as follows:
‌Ag+‌matches with ‌96500Cmol−1
‌Mg2+‌ matches with ‌193000Cmol−1
‌Al3+‌ matches with ‌289500Cmol−1
‌Ti4+‌ matches with ‌386000Cmol−1