The number of cyclic ketones of molecular formula `C_(3)H_(4)O` are:

Options

A. 2
B. 1
C. 3
D. 4

Answer

To determine the number of cyclic ketones with the molecular formula C₃H₄O, we can follow these steps:

### Step 1: Understand the molecular formula
The molecular formula C₃H₄O indicates that there are 3 carbon atoms, 4 hydrogen atoms, and 1 oxygen atom.

### Step 2: Identify the structure of cyclic ketones
Cyclic ketones are compounds that contain a carbonyl group (C=O) within a ring structure. For a cyclic ketone, the carbonyl carbon must be part of the ring.

### Step 3: Draw possible cyclic structures
For C₃H₄O, the simplest cyclic structure we can form is a cyclopropane ring (3 carbon atoms in a cycle). We can place the carbonyl group on one of the carbons in the ring.

### Step 4: Construct the cyclic ketone
1. Draw a triangle to represent the cyclopropane.
2. Label the vertices of the triangle as carbon atoms (C1, C2, C3).
3. Place a carbonyl (C=O) on one of the carbon atoms (for example, C1).
4. Adjust the hydrogen atoms accordingly to ensure that the total number of hydrogen atoms is 4.

The structure will look like this:
- C1 has a double bond with O (C=O) and one hydrogen (H).
- C2 and C3 each have two hydrogens (H₂).

### Step 5: Confirm the molecular formula
Now, let's check:
- Total Carbons (C): 3
- Total Hydrogens (H): 4
- Total Oxygens (O): 1

This confirms that the structure fits the molecular formula C₃H₄O.

### Conclusion
Thus, there is only **one cyclic ketone** that can be formed with the molecular formula C₃H₄O.

### Final Answer
The number of cyclic ketones of molecular formula C₃H₄O is **1**.

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