When ethyl hydrogensulphate is heated at `140^(@)C` with excess of alcohol, the product formed is

Options

A. ethane
B. ethylene
C. diethyl ether
D. diethyl sulfate

Explanation

To solve the question of what product is formed when ethyl hydrogen sulfate is heated with excess alcohol at 140°C, we can follow these steps:

### Step 1: Identify the Reactants
The reactant in this case is ethyl hydrogen sulfate, which has the chemical formula C2H5HSO4. We are also using excess alcohol, which we can assume to be ethanol (C2H5OH) for this reaction.

### Step 2: Understand the Reaction Conditions
The reaction is taking place at a temperature of 140°C. This temperature is significant as it can facilitate the reaction between ethyl hydrogen sulfate and the alcohol.

### Step 3: Predict the Reaction Type
The reaction between an alcohol and an alkyl hydrogen sulfate typically leads to the formation of an ether. In this case, we are looking at the formation of diethyl ether. The mechanism of this reaction is an SN2 mechanism, which involves the nucleophilic substitution of the alcohol on the alkyl hydrogen sulfate.

### Step 4: Write the Reaction Equation
When ethyl hydrogen sulfate reacts with ethanol, the following reaction occurs:
\[ \text{C2H5HSO4} + \text{C2H5OH} \rightarrow \text{C2H5OC2H5} + \text{H2SO4} \]
This shows that diethyl ether (C2H5OC2H5) and sulfuric acid (H2SO4) are formed.

### Step 5: Identify the Product
From the reaction, we can see that the main product formed is diethyl ether (C2H5OC2H5).

### Conclusion
Thus, the product formed when ethyl hydrogen sulfate is heated at 140°C with excess alcohol is **diethyl ether**.

### Final Answer
The correct option is **C. diethyl ether**.

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