Which of the following substances is commonly used as a base in deodorants?

• A. carrageenan
• B. sodium lauryl sulfate
• C. magnesium hydroxide
• D. sorbitol

Answer: (C)

Verified step by step guidance

1. Understand that bases are substances that can accept protons (H+) or donate electron pairs, and they often neutralize acids.
2. Review the chemical nature of each substance listed: carrageenan is a polysaccharide used as a thickener, sodium lauryl sulfate is a surfactant (detergent), magnesium hydroxide is a metal hydroxide known for its basic properties, and sorbitol is a sugar alcohol used as a sweetener.
3. Recognize that deodorants often use bases to neutralize acidic odors and reduce skin irritation, so the base must be mildly alkaline and safe for topical use.
4. Identify magnesium hydroxide as a common base used in deodorants because it can neutralize acids and is gentle on the skin.
5. Conclude that among the options, magnesium hydroxide is the substance commonly used as a base in deodorants.