Which is the best practice recommended in the safety video when mixing an acid or a base with a solvent?

• A. Add solvent to the acid or base quickly to minimize reaction time.
• B. Add acid or base and solvent simultaneously to the container.
• C. Mix acid or base and solvent together rapidly to ensure complete mixing.
• D. Always add acid or base to the solvent slowly while stirring.

Answer: (D)

Verified step by step guidance

1. Understand that when mixing acids or bases with solvents (usually water), the process is exothermic, meaning it releases heat.
2. Recognize that adding solvent to a concentrated acid or base can cause the mixture to splash or boil violently due to rapid heat release.
3. Therefore, the safest practice is to add the acid or base slowly to the solvent while stirring continuously to dissipate heat evenly and prevent splashing.
4. Avoid adding acid or base and solvent simultaneously or mixing them rapidly, as this can cause dangerous reactions or splattering.
5. Remember the safety rule: 'Always add acid or base to the solvent slowly while stirring' to minimize risk and ensure safe handling.