A hydrocarbon (V.D. = 27) containing C = 88.88% decolourised `KMnO_4` solution and bromine water with evolution of HBr. It gave no precipitate with either ammoniacal silver nitrate or cuprous chloride solution. When treated with dil. `H_2 SO_4` in the presence of `HgSO_4`, it gave methyl ethyl ketone. What is the hydrocarbon ?

Explanation

To solve the question regarding the hydrocarbon with a vapor density of 27, we will follow these steps:

### Step 1: Calculate the Molecular Mass
The vapor density (V.D.) is given as 27. The molecular mass (M) can be calculated using the formula:
\[ M = 2 \times \text{V.D.} \]
Substituting the given value:
\[ M = 2 \times 27 = 54 \, \text{g/mol} \]

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