When 50% solution of `H_(2)SO_(4)` is electrolysed by passing a current of high density at low temperature the main products of electrolysis are:

Options

A. Oxygen & Hydrogen
B. `H_(2)` and peroxy disuphuric acid
C. `H_(2) and SO_(2)`
D. `O_(2)` and peroxy disulphuric acid

Answer

To solve the problem of identifying the main products of electrolysis of a 50% solution of sulfuric acid (H₂SO₄), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Electrolysis of H₂SO₄**:
- When sulfuric acid is dissolved in water, it dissociates into hydrogen ions (H⁺) and bisulfate ions (HSO₄⁻). The electrolysis process involves the movement of these ions towards the electrodes.

2. **Identifying the Cathode Reaction**:
- At the cathode, cations (H⁺ ions) migrate towards the negatively charged electrode. Each H⁺ ion gains an electron (reduction) to form hydrogen gas (H₂).
- The reaction at the cathode can be represented as:
\[ 2H^+ + 2e^- \rightarrow H_2(g) \]
- Thus, hydrogen gas is produced at the cathode.

3. **Identifying the Anode Reaction**:
- At the anode, anions (HSO₄⁻ ions) migrate towards the positively charged electrode. The oxidation of HSO₄⁻ ions occurs, leading to the formation of peroxodisulfuric acid (H₂S₂O₈).
- The reaction at the anode can be represented as:
\[ 2HSO_4^- \rightarrow H_2S_2O_8 + 2e^- \]
- Therefore, peroxodisulfuric acid is produced at the anode.

4. **Summarizing the Overall Reaction**:
- The overall reaction for the electrolysis of 50% H₂SO₄ can be summarized as:
\[ 2H_2SO_4 \rightarrow H_2(g) + H_2S_2O_8 \]
- This indicates that the main products of the electrolysis are hydrogen gas (H₂) and peroxodisulfuric acid (H₂S₂O₈).

5. **Choosing the Correct Option**:
- From the options provided:
1. Oxygen and hydrogen
2. Hydrogen and peroxide disulfuric acid
3. Hydrogen and SO₂ gas
4. Oxygen and peroxide disulfuric acid
- The correct answer is option 2: Hydrogen and peroxide disulfuric acid (H₂S₂O₈).

### Final Answer:
The main products of electrolysis of a 50% solution of H₂SO₄ are hydrogen gas (H₂) and peroxodisulfuric acid (H₂S₂O₈).

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