Which of the two: `O_(2)NCH_(2)CH_(2)O^(–)` or `CH_(3)CH_(2)O^(–)` is expected to be more stable and why ?

Explanation

To determine which of the two compounds, `O_(2)NCH_(2)CH_(2)O^(–)` or `CH_(3)CH_(2)O^(–)`, is more stable, we need to analyze the effects of the substituents on the stability of the negatively charged oxygen atom in each compound.

### Step-by-Step Solution:

1. **Identify the Groups Present**:
- In the first compound, `O_(2)NCH_(2)CH_(2)O^(–)`, there is a nitro group (`NO2`) attached to the carbon chain.
- In the second compound, `CH_(3)CH_(2)O^(–)`, there are ethyl (`C2H5`) and methyl (`CH3`) groups.

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