`CH_3 CONH_2` is a weaker base than `CH_3 CH_2 NH_2`.

Explanation

To determine why `CH3CONH2` (acetamide) is a weaker base than `CH3CH2NH2` (ethylamine), we can analyze the structures and the electronic effects involved in both compounds. Here’s a step-by-step breakdown of the reasoning:

### Step 1: Draw the Structures
1. **Acetamide (CH3CONH2)**: The structure consists of a carbonyl group (C=O) attached to a nitrogen atom which has two hydrogens and one methyl group attached.
2. **Ethylamine (CH3CH2NH2)**: This structure consists of a nitrogen atom bonded to two ethyl groups (C2H5) and two hydrogens.

### Step 2: Identify the Lone Pair on Nitrogen
- In both compounds, the nitrogen atom has a lone pair of electrons. This lone pair is crucial for the basicity of the amines, as it can be donated to accept protons (H+).
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