Which safety rule is most important to follow when smelling the product of a chemical reaction in the laboratory?

• A. Place your nose directly over the container and inhale deeply.
• B. Always use the wafting technique to direct vapors toward your nose.
• C. Remove your safety goggles before smelling the product.
• D. Smell the product only after mixing all chemicals together.

Answer: (B)

Verified step by step guidance

1. Understand that safety in the chemistry lab is paramount, especially when dealing with unknown or potentially hazardous chemicals.
2. Recognize that directly inhaling vapors by placing your nose over a container can expose you to harmful or concentrated fumes, which is unsafe.
3. Learn the wafting technique: gently wave your hand over the opening of the container to direct a small amount of vapor toward your nose without directly inhaling from the container.
4. Remember that safety goggles should always be worn in the lab to protect your eyes from splashes or harmful vapors, so never remove them when smelling chemicals.
5. Avoid smelling chemicals after mixing unless you are sure of the reaction products and their safety; always follow proper lab protocols and instructor guidance.