Which of the followingis not correct?

Options

A. The metallic conduction is due to the movement of electrons in the metal
B. The electrolytic conduction is due to the movement of ions in the solution
C. The current carrying ions are not necessarily discharged at the electrodes
D. The metallic conduction increases with the increase in temperature, whereas that of electrolytic conduction decreases with temperature.

Answer

To determine which of the following statements is not correct, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Metallic Conduction**:
- Metallic conduction occurs due to the movement of free electrons in metals. For example, in sodium (Na), the atomic number is 11, and its electronic configuration is 1s² 2s² 2p⁶ 3s¹. The single unpaired electron in the 3s orbital can move freely, allowing sodium to conduct electricity.
- **Conclusion**: This statement is correct.

2. **Understanding Electrolytic Conduction**:
- Electrolytic conduction involves the movement of ions in a solution. For instance, when NaCl is dissolved in water, it dissociates into Na⁺ and Cl⁻ ions. These ions facilitate the conduction of electricity in the solution.
- **Conclusion**: This statement is also correct.

3. **Current Carrying Ions and Discharge**:
- The statement claims that current-carrying ions are not necessarily discharged at the electrode. This is true because if there is insufficient energy, the ions may not discharge even though they are carrying current.
- **Conclusion**: This statement is correct.

4. **Effect of Temperature on Conductivity**:
- The statement claims that metallic conduction increases with an increase in temperature. However, as temperature increases, the thermal velocity of electrons also increases, which leads to more collisions with the lattice structure of the metal. This results in increased resistivity and decreased conductivity.
- Therefore, the statement that metallic conduction increases with temperature is incorrect.
- **Conclusion**: This statement is not correct.

5. **Electrolytic Conduction and Temperature**:
- The statement mentions that electrolytic conduction decreases with temperature. However, electrolytic conduction generally increases with temperature because higher temperatures provide more energy to the ions, allowing them to move more freely.
- **Conclusion**: This statement is also incorrect.

### Final Conclusion:
The statement that is not correct is **D**: "The metallic conduction increases with increase in temperature."