An alkene is formed from a carbocation by

Options

A. Elimination of a `H^(+)` ion
B. Elimination of `H^(-)` ion
C. Addtion of a `H^(+)` ion
D. Addition of a `H^(-)` ion

Explanation

To understand how an alkene is formed from a carbocation, let's break down the process step by step.

### Step 1: Identify the Carbocation
We start with a carbocation, which is a positively charged carbon atom. For example, let's consider the carbocation CH3-CH2+.

### Step 2: Stability of the Carbocation
Carbocations are unstable and will seek to become more stable. One way to achieve stability is through the loss of a hydrogen atom.

### Step 3: Elimination of a Hydrogen Atom
The carbocation (CH3-CH2+) will eliminate a hydrogen atom (H+) from the adjacent carbon atom. This results in the formation of a double bond between the two carbon atoms.

### Step 4: Formation of the Alkene
After the elimination of the hydrogen ion (H+), we are left with a double bond between the two carbon atoms. The resulting compound is an alkene. In this case, we form ethylene (CH2=CH2).

### Step 5: Write the Final Equation
The overall reaction can be summarized as:
CH3-CH2+ → CH2=CH2 + H+

Thus, the alkene is formed through the elimination of a hydrogen ion from the carbocation.

### Final Answer
An alkene is formed from a carbocation by the elimination of a hydrogen ion, resulting in the formation of a double bond.

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