In which of the following species odd electron participate easily in dimerization .

Options

A. (a)`ClO_(2)`
B. (b)`O_(2)^(-)`
C. (c)`NO_(2)`
D. (d)`NO`

Answer

To solve the question of which species with an odd number of electrons participates easily in dimerization, we will analyze the given species one by one.

### Step-by-Step Solution:

1. **Identify the Species**: We have four species to analyze: ClO2, O2^-, NO2, and another NO2.

2. **Determine the Number of Valence Electrons**:
- **ClO2**: Chlorine (Cl) has 7 valence electrons, and each oxygen (O) has 6 valence electrons. In ClO2, there are two oxygen atoms contributing a total of 12 electrons. The total number of electrons is 7 (from Cl) + 12 (from 2 O) = 19 electrons. Since 19 is an odd number, ClO2 has an odd number of electrons.
- **O2^-**: Each oxygen has 6 valence electrons, and with the extra negative charge, we add one more electron. Therefore, O2^- has 6 + 6 + 1 = 13 electrons, which is also odd.
- **NO2**: Nitrogen (N) has 5 valence electrons, and each oxygen has 6. Thus, NO2 has 5 + 6 + 6 = 17 electrons, which is odd.
- **Another NO2**: This is the same as the previous species, so it also has 17 electrons, which is odd.

3. **Check for Dimerization**: Dimerization is the process where two molecules combine to form a larger molecule. For dimerization to occur easily, the species should have a large size to minimize steric hindrance.
- **ClO2**: Being larger due to the presence of chlorine, it can participate in dimerization without significant steric hindrance.
- **O2^-**: Although it has an odd number of electrons, it is smaller and may face steric hindrance.
- **NO2**: While it has an odd number of electrons, it is also smaller compared to ClO2, which may limit its ability to dimerize easily.

4. **Conclusion**: Among the species analyzed, ClO2 is the one that can easily participate in dimerization due to its larger size and lesser steric hindrance.

### Final Answer:
The species in which odd electrons participate easily in dimerization is **ClO2**.

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