Which of the following is an example for unsaturated fatty acid

Options

A. Palmitic acid
B. Stearic acid
C. Acetic acid
D. Linoleic acid

Answer

To determine which of the given options is an example of an unsaturated fatty acid, we need to analyze the chemical formulas of each option and see if they fit the general formula for saturated fatty acids.

### Step-by-Step Solution:

1. **Understand the General Formula for Saturated Fatty Acids**:
The general formula for a saturated fatty acid is \( C_nH_{2n}O_2 \), where \( n \) is the number of carbon atoms.

2. **Analyze Each Option**:
We will check each option against the general formula.

- **Option 1: Palmitic Acid**
- Formula: \( C_{16}H_{32}O_2 \)
- Here, \( n = 16 \).
- Checking: \( H = 2n = 2 \times 16 = 32 \).
- Conclusion: Palmitic acid follows the formula, hence it is a saturated fatty acid.

- **Option 2: Stearic Acid**
- Formula: \( C_{18}H_{36}O_2 \)
- Here, \( n = 18 \).
- Checking: \( H = 2n = 2 \times 18 = 36 \).
- Conclusion: Stearic acid follows the formula, hence it is a saturated fatty acid.

- **Option 3: Acetic Acid**
- Formula: \( C_{2}H_{4}O_{2} \)
- Here, \( n = 2 \).
- Checking: \( H = 2n = 2 \times 2 = 4 \).
- Conclusion: Acetic acid follows the formula, hence it is a saturated fatty acid.

- **Option 4: Linoleic Acid**
- Formula: \( C_{18}H_{32}O_2 \)
- Here, \( n = 18 \).
- Checking: \( H = 2n = 2 \times 18 = 36 \).
- Since the actual hydrogen count is 32, it does not fit the saturated fatty acid formula.
- Conclusion: Linoleic acid does not follow the formula, hence it is an unsaturated fatty acid.

3. **Final Conclusion**:
The only option that is an unsaturated fatty acid is **Linoleic Acid**.