Oxidation takes place with -

Options

A. Gain of electrons
B. Loss of electrons
C. Increase in the valency of negative part
D. Decrease in the valency of positive part

Answer

To determine what oxidation entails, we can analyze the options provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Oxidation**:
- Oxidation is a chemical process that involves a change in the oxidation state of an element. It is often associated with the loss of electrons.

2. **Analyzing the Options**:
- **Option 1: Gain of Electron**: This is incorrect because gaining electrons corresponds to reduction, not oxidation.
- **Option 2: Loss of Electron**: This is correct. Oxidation is defined as the loss of electrons by an atom or ion, leading to an increase in its oxidation state.
- **Option 3: Increase in the Valency of Negative Part**: This is misleading. Valency refers to the combining capacity of an element, and while oxidation can involve changes in oxidation states, it does not directly correlate with valency changes in a straightforward manner.
- **Option 4: Increase in the Valency of Positive Part**: Similar to option 3, this is not a definitive characteristic of oxidation. While oxidation can affect the oxidation state, it does not necessarily mean that valency increases.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option 2: Loss of Electron**. This aligns with the fundamental definition of oxidation in redox reactions.

### Final Answer:
**Oxidation takes place with the loss of electrons.**

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