A substance which can act both as an antiseptic and disinfectant is

Options

A. Aspirin
B. Phenol
C. Analgin
D. Sodium pentothal

Answer

**Step-by-Step Solution:**

1. **Understanding Antiseptics and Disinfectants:**
- Antiseptics are substances that prevent the growth of disease-causing microorganisms and are safe for use on living tissues.
- Disinfectants are chemical agents used to destroy or inhibit the growth of harmful microorganisms on inanimate objects.

2. **Identifying a Common Substance:**
- We need to find a substance that can serve both purposes—acting as an antiseptic for living tissues and as a disinfectant for surfaces.

3. **Considering Phenol:**
- Phenol is a well-known chemical compound that has properties making it effective as both an antiseptic and a disinfectant.
- When used in low concentrations (around 0.2%), phenol can be applied to skin as an antiseptic.
- At higher concentrations (around 1%), it can be used as a disinfectant on surfaces.

4. **Effectiveness Against Microorganisms:**
- Phenol is effective against a wide range of microorganisms, including bacteria, fungi, and some viruses, which supports its use in both antiseptic and disinfectant roles.

5. **Conclusion:**
- Based on the properties and effectiveness of phenol, we conclude that the substance which can act both as an antiseptic and disinfectant is **phenol**.

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