Which of the following statements is invalid-

Options

A. the more stable the carbocation the faster it is formed
B. propyl cation changes to more stable isopropyl carbonation by 1,2 shift of a hydrogen
C. isopropyl chloride reacts with sodium ethoxide to form 1– ethoxypropane
D. propyl halides reacts with sodium ethoxide to form 1- ethoxypropane

Answer

To determine which of the statements is invalid, let's analyze each statement step by step.

### Step 1: Analyze the First Statement
**Statement:** The more stable the carbocation, the faster it is formed.

**Analysis:** This statement is true. In an SN1 reaction, the stability of the carbocation plays a crucial role. More stable carbocations (like tertiary carbocations) form faster than less stable ones (like primary carbocations).

**Conclusion:** This statement is correct.

### Step 2: Analyze the Second Statement
**Statement:** Propyl cation changes to more stable isopropyl carbocation by 1-2 shift of hydrogen.

**Analysis:** The propyl cation (CH3-CH2-CH2^+) can undergo a 1,2-hydride shift to form the isopropyl cation (CH3-CH^+-CH3). This shift results in a more stable secondary carbocation.

**Conclusion:** This statement is also correct.

### Step 3: Analyze the Third Statement
**Statement:** Isopropyl chloride reacts with sodium ethoxide to give 1-ethoxy propane.

**Analysis:** In this reaction, isopropyl chloride (CH3-CHCl-CH3) reacts with sodium ethoxide (NaOC2H5) through the Williamson ether synthesis. The product formed is 2-ethoxy propane (CH3-CH(O-C2H5)-CH3), not 1-ethoxy propane.

**Conclusion:** This statement is incorrect.

### Step 4: Analyze the Fourth Statement
**Statement:** Propyl aniline reacts with sodium ethoxide to give 1-ethoxy propane.

**Analysis:** Propyl aniline (C3H7-NH2) can react with sodium ethoxide (NaOC2H5) to form 1-ethoxy propane (C3H7-O-C2H5) through a similar ether formation process.

**Conclusion:** This statement is correct.

### Final Conclusion
The invalid statement among the options is the third statement: "Isopropyl chloride reacts with sodium ethoxide to give 1-ethoxy propane."

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