Electron affinity of :

Options

A. carbon is greater than oxygen
B. oxygen is greater than flourine
C. iodine is higher than bromine
D. bromine is lesser than chlorine

Answer

### Step-by-Step Solution:

1. **Understanding Electron Affinity**:
- Electron affinity is defined as the amount of energy released when an electron is added to a neutral atom or molecule in the gaseous state. It is a measure of the tendency of an atom to accept an electron.

2. **Trends in Electron Affinity**:
- As we move from left to right across a period in the periodic table, the electron affinity generally increases. This is because the atomic size decreases, leading to a stronger attraction between the nucleus and the added electron.
- Conversely, as we move down a group, the electron affinity typically decreases. This is due to the increase in atomic size, which results in a weaker attraction between the nucleus and the added electron.

3. **Comparing Elements**:
- The question provides options to compare the electron affinity of various elements: carbon, oxygen, iodine, bromine, and chlorine.

4. **Analyzing the Options**:
- **Option 1**: Carbon > Oxygen
- This is incorrect. Oxygen has a higher electron affinity than carbon because it is to the right of carbon in the periodic table.
- **Option 2**: Oxygen > Fluorine
- This is also incorrect. Fluorine has a higher electron affinity than oxygen.
- **Option 3**: Iodine > Bromine
- This is incorrect. Bromine has a higher electron affinity than iodine since electron affinity decreases down the group.
- **Option 4**: Bromine < Chlorine
- This is correct. Chlorine has a higher electron affinity than bromine due to the trend of decreasing electron affinity down the group.

5. **Conclusion**:
- The correct answer is that bromine has a lesser electron affinity than chlorine. Therefore, the fourth option is the right choice.