When the vapours of tertiary butyl alcohol are passed through heated copper at 578 K, the product formed is

Options

A. but-2-ene
B. butan-2-one
C. 2-methylpropene
D. butanal

Explanation

To solve the problem, we need to understand the reaction that occurs when tertiary butyl alcohol is passed over heated copper. Let's break it down step by step:

### Step 1: Identify the structure of tertiary butyl alcohol
Tertiary butyl alcohol (TBA) has the chemical formula (CH₃)₃COH. It consists of four carbon atoms, where the hydroxyl (OH) group is attached to a carbon that is connected to three other carbon atoms.

### Step 2: Understand the reaction conditions
The reaction occurs at a temperature of 578 K in the presence of heated copper. Copper acts as a dehydrating agent in this reaction, which means it will facilitate the removal of water (H₂O) from the alcohol.

### Step 3: Dehydration of tertiary butyl alcohol
When tertiary butyl alcohol is heated, the hydroxyl group (OH) can be removed along with a hydrogen atom (H) from the adjacent carbon. This process is known as dehydration.

### Step 4: Write the dehydration reaction
The dehydration of tertiary butyl alcohol can be represented as follows:
- (CH₃)₃COH → (CH₃)₂C=CH₂ + H₂O

In this reaction, the product formed is 2-methylpropene (also known as isobutylene), which is an alkene.

### Step 5: Identify the product
The product formed from the dehydration of tertiary butyl alcohol when passed over heated copper at 578 K is 2-methylpropene.

### Final Answer
The product formed is **2-methylpropene**.

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