(A) Ammonolysis of alkyl halides is not a suitable method for the preparation of pure primary amines.
(R) Ammonolysis of alkyl halides yields mainly secondary amines.

Options

A. If both A and R are correct and R is the correct explanation of A.
B. If both A and R are correct and R is not the correct explanation of A.
C. If A is the correct but R is incorect.
D. If A is the incorrect but R is corect.

Answer

To analyze the given statements regarding the ammonolysis of alkyl halides, we will break down the reasoning step by step.

### Step 1: Understanding Ammonolysis
Ammonolysis is a reaction where an alkyl halide reacts with ammonia (NH₃) to form amines. The general reaction can be represented as:
\[ R-X + NH_3 \rightarrow R-NH_2 + HX \]
where \( R-X \) is the alkyl halide and \( HX \) is the byproduct (hydrogen halide).

**Hint:** Recall the basic reaction mechanism of nucleophilic substitution, where ammonia acts as a nucleophile.

### Step 2: Formation of Primary Amines
When ammonia reacts with an alkyl halide, it can theoretically produce primary amines (RNH₂). However, the formation of primary amines depends on the concentration of the reactants.

**Hint:** Consider the role of reactant concentrations in determining the products of a reaction.

### Step 3: Excess of Alkyl Halide
If the alkyl halide (R-X) is in excess, it can react with the primary amine (RNH₂) formed in the first step to produce secondary amines (R₂NH):
\[ R-X + R-NH_2 \rightarrow R_2-NH + HX \]
This means that the presence of excess alkyl halide can lead to the formation of secondary amines rather than allowing the reaction to stop at the primary amine stage.

**Hint:** Think about how excess reactants can shift the reaction equilibrium and lead to different products.

### Step 4: Excess of Ammonia
If ammonia is in excess, the reaction is more likely to yield primary amines, as there are more ammonia molecules available to react with the alkyl halide. However, even in this case, there is still a possibility of forming secondary and tertiary amines if the alkyl halide is reactive enough.

**Hint:** Reflect on how the stoichiometry of the reactants influences the final products.

### Step 5: Conclusion on Statement A
Given the above reasoning, it is correct to state that ammonolysis of alkyl halides is not a suitable method for preparing pure primary amines, as secondary and tertiary amines can also be formed depending on the conditions.

### Step 6: Conclusion on Statement R
The assertion that ammonolysis yields mainly secondary amines is misleading. While secondary amines can be formed, it is not accurate to say they are the main product without specifying the conditions of the reaction.

### Final Answer
- Statement (A) is correct: Ammonolysis of alkyl halides is not a suitable method for the preparation of pure primary amines.
- Statement (R) is incorrect: Ammonolysis does not primarily yield secondary amines.

Thus, the correct conclusion is that A is correct, but R is incorrect.

### Overall Conclusion
The answer is option C: A is correct but R is incorrect.