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

Explanation

`O_(2)NCH_(2)CH_(2)O^(-)` is more stable because `-NO_(2)` group with `- I` effect disperses the negaitive charge on the anion. On the other hand, `CH_(3)CH_(2^(-))` group with `+ I` effect increases the magnitude of the negative charge on the anion and thus destabilises it.