Arrange the following in decreasing order of their basic strength: ammonia, triethylamine, aniline, ethylamine and diethylamine.

Explanation

To arrange the compounds ammonia, triethylamine, aniline, ethylamine, and diethylamine in decreasing order of their basic strength, we need to analyze the influence of inductive effects and the availability of the lone pair of electrons on the nitrogen atom in each compound.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds we need to compare are:
- Ammonia (NH₃)
- Triethylamine (N(C₂H₅)₃)
- Aniline (C₆H₅NH₂)
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