Give the decreasing order of basic strength of the following :
(a) `NH_3`
(b) `NH_2OH`
( c) `NH_2-NH_2`.

Explanation

To determine the decreasing order of basic strength of the compounds NH3 (ammonia), NH2OH (hydroxylamine), and NH2NH2 (hydrazine), we need to analyze the ability of each compound to donate a lone pair of electrons. Basic strength is influenced by the availability of lone pairs on the nitrogen atom and the presence of any electron-withdrawing or electron-donating groups.

### Step-by-Step Solution:

1. **Identify the Compounds and Their Structures**:
- **NH3 (Ammonia)**: Contains one nitrogen atom with one lone pair of electrons.
- **NH2OH (Hydroxylamine)**: Contains one nitrogen atom with two hydrogen atoms and one hydroxyl (OH) group.
- **NH2NH2 (Hydrazine)**: Contains two nitrogen atoms, each with one lone pair of electrons.
...