When preparing solutions, which practice is recommended for combining acid and base?

When preparing solutions, which practice is recommended for combining acid and base?

• A. Add acid to base.
• B. Add base to acid.
• C. Add acid to solvent.
• D. Skip measurements and calculations.

Answer: (A)

When mixing acid and base, the reaction is exothermic and points of contact can heat up quickly. Adding acid into a base solution and stirring slowly helps distribute the acid as it reacts, so the heat is absorbed by the larger volume of base and the mixture stays more uniform. This approach reduces the chance of local overheating, splashing, or concentration hot spots and makes it easier to reach the desired final concentration safely and accurately. Adding base to acid can produce vigorous, uneven heating right where the acid is concentrated, which is harder to control. Adding acid to solvent misses the presence of the base altogether and can lead to improper mixing or unintended pH changes. Skipping measurements and calculations is not a safe or reliable way to prepare a solution.

When mixing acid and base, the reaction is exothermic and points of contact can heat up quickly. Adding acid into a base solution and stirring slowly helps distribute the acid as it reacts, so the heat is absorbed by the larger volume of base and the mixture stays more uniform. This approach reduces the chance of local overheating, splashing, or concentration hot spots and makes it easier to reach the desired final concentration safely and accurately.

Adding base to acid can produce vigorous, uneven heating right where the acid is concentrated, which is harder to control. Adding acid to solvent misses the presence of the base altogether and can lead to improper mixing or unintended pH changes. Skipping measurements and calculations is not a safe or reliable way to prepare a solution.