Arrange the following amines in the order of increasing basicity :-

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Answer

To arrange the given amines in the order of increasing basicity, we need to consider the structure of each amine and the effects of substituents on their basicity. Here’s a step-by-step solution:

### Step 1: Identify the Types of Amines
We have to categorize the amines into aliphatic and aromatic amines. Aliphatic amines (like methyl amine) are generally more basic than aromatic amines (like aniline and its derivatives).

### Step 2: Analyze the Given Amines
Assuming we have the following amines:
1. Methylamine (CH₃NH₂)
2. Aniline (C₆H₅NH₂)
3. Para-methyl oxyaniline (C₆H₄(NH₂)(OCH₃))
4. Para-nitroaniline (C₆H₄(NH₂)(NO₂))

### Step 3: Determine Basicity Influences
- **Aliphatic Amines**: Methylamine is an aliphatic amine and is more basic due to the electron-donating effect of the alkyl group (CH₃).
- **Aromatic Amines**: Aniline is less basic than methylamine because the lone pair on the nitrogen is delocalized into the aromatic ring, reducing its availability to accept protons.
- **Substituted Aromatic Amines**:
- Para-methyl oxyaniline has a methoxy group (OCH₃) which is an electron-donating group, making it more basic than aniline.
- Para-nitroaniline has a nitro group (NO₂), which is an electron-withdrawing group, making it the least basic among the given amines.

### Step 4: Arrange in Order of Increasing Basicity
Based on the analysis:
1. Para-nitroaniline (least basic)
2. Aniline
3. Para-methyl oxyaniline
4. Methylamine (most basic)

Thus, the order of increasing basicity is:
**Para-nitroaniline < Aniline < Para-methyl oxyaniline < Methylamine**

### Final Answer
The order of increasing basicity is:
**Para-nitroaniline < Aniline < Para-methyl oxyaniline < Methylamine**