In the chemistry lab, a student immersed two platinum electrodes in a

1.	In the chemistry lab, a student immersed two platinum electrodes in a solution of CuSO4 and electric current was passed through the solution. After sometime he noticed that the colour of CuSO4 disappeares with the evolution of a gas at the electrode. In his Practical Log, he recorded that the colourless solution contains H2SO4 .1. Is it true? 2. Comment on his findings and justify your answer.
Answer» 1. Yes. 2. When aqueous CuSO₄ solution is electrolysed using Pt electrodes, Cu is deposited at the cathode and O₂ is liberated at the anode. CuSO₄ (aq) → Cu²⁺(aq) + SO₄^2-(aq) Cu²⁺ (aq) + 2\(\bar e\) → Cu(s) (at cathode) H₂O(l) → 2H+(aq) + 1/2 O₂(g) + 2\(\bar e\) (at anode) Thus, H₂SO₄ is formed as the secondary product.

In the chemistry lab, a student immersed two platinum electrodes in a solution of CuSO4 and electric current was passed through the solution. After sometime he noticed that the colour of CuSO4 disappeares with the evolution of a gas at the electrode. In his Practical Log, he recorded that the colourless solution contains H2SO4 .1. Is it true? 2. Comment on his findings and justify your answer.

Answer»

1. Yes.

2. When aqueous CuSO₄ solution is electrolysed using Pt electrodes, Cu is deposited at the cathode and O₂ is liberated at the anode.

CuSO₄ (aq) → Cu²⁺(aq) + SO₄^2-(aq)

Cu²⁺ (aq) + 2\(\bar e\) → Cu(s) (at cathode)

H₂O(l) → 2H+(aq) + 1/2 O₂(g) + 2\(\bar e\) (at anode)

Thus, H₂SO₄ is formed as the secondary product.

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