Pentene-1 with HCl gives

Options

A. 3-chloropentane
B. 2-chloropentane
C. 1,2-dichloropentane
D. 1-chloropentane.

Answer

To solve the question regarding the reaction of pent-1-ene with HCl, we can follow these steps:

### Step 1: Identify the Reactants
The reactant in this case is pent-1-ene (C5H10), which is an alkene with a double bond between the first and second carbon atoms.

### Step 2: Understand the Reaction Type
The reaction between alkenes and hydrogen halides (like HCl) typically follows Markovnikov's rule. This rule states that when HX (where X is a halogen) adds to an alkene, the hydrogen atom will attach to the carbon with the greater number of hydrogen atoms (the more substituted carbon), while the halogen will attach to the carbon with fewer hydrogen atoms.

### Step 3: Draw the Structure of Pent-1-ene
Pent-1-ene can be represented as:
```
CH2=CH-CH2-CH2-CH3
```

### Step 4: Add HCl to the Alkene
When HCl is added to pent-1-ene, the double bond breaks. According to Markovnikov's rule, the hydrogen from HCl will attach to the first carbon (C1), and the chlorine will attach to the second carbon (C2).

### Step 5: Identify the Product
After the addition of HCl, the structure of the product will be:
```
CH3-CHCl-CH2-CH2-CH3
```
This compound is 2-chloropentane, as the chlorine atom is attached to the second carbon of the pentane chain.

### Step 6: Write the Final Answer
The product of the reaction between pent-1-ene and HCl is 2-chloropentane.

### Final Answer:
**2-chloropentane**

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