When electric current is passed through Copper (II) sulphate solution for several hours as shown in the diagram below, a gas that relights a glowing...

When electric current is passed through Copper (II) sulphate solution for several hours as shown in the diagram below, a gas that relights a glowing splint is produced at electrode R.

(i) Which of the electrodes is the cathode? Give a reason.
(ii) State and explain the observations that would be made at the electrodes.

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(i)S
Because oxygen gas is given out at electrode R thus electrode R is the anode since OH- ions which give oxygen migrate
there.
(ii)4OH-(aq) ……………………>2H₂O(l) + O₂(g) + 4e-
(iii)A brown solid is deposited on electrode S – this is because the CU2+ ions in solution gain electrons at S to form Copper metal as shown in the following equation.
CU²⁺(aq) + 2e-……………………>CU(s) brown

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sharon kalunda answered the question on March 28, 2019 at 08:51

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