Which one of the following substances is most likely to be used as soap ?

Options

A. `CH_(3)(CH_(2))_(12)COOCH_(3)`
B. `CH_(3)(CH_(2))_(5)O(CH_(2))_(5)CH_(3)`
C. `CH_(3)(CH_2)_(12)COONa`
D. `CH_(3)(CH_(2))_(12)CHCl_(2)`

Explanation

To determine which substance is most likely to be used as soap, we need to understand what soap is and its chemical composition.

### Step-by-Step Solution:

1. **Understanding Soap**: Soap is typically defined as the sodium or potassium salt of a long-chain carboxylic acid (fatty acid). This means that for a substance to be considered soap, it should contain either sodium or potassium ions and a long-chain fatty acid.

2. **Identifying the Components**: The general formula for soap can be represented as RCOONa or RCOOK, where R represents a long hydrocarbon chain (usually containing 12 to 18 carbon atoms). The carboxylic acid part (RCOO-) is what gives soap its cleaning properties.

3. **Analyzing the Options**:
- Look at the given options (not provided in the question, but let's assume there are four options).
- Identify which options contain sodium (Na) or potassium (K) as part of their chemical structure.
- Check if any of the options represent a long-chain carboxylic acid.

4. **Selecting the Right Option**:
- If one of the options is a sodium or potassium salt of a long-chain carboxylic acid (like C17H35COONa or C17H35COOK), that would be the most likely candidate for soap.
- If other options do not contain sodium or potassium or do not represent long-chain fatty acids, they can be eliminated.

5. **Conclusion**: Based on the analysis, the option that contains sodium or potassium and represents a long-chain fatty acid is the correct answer.

### Final Answer:
The substance most likely to be used as soap is the one that is a sodium or potassium salt of a long-chain carboxylic acid, which corresponds to option 3 in this case.

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