Which dilution practice is unsafe when handling concentrated acids?

Which dilution practice is unsafe when handling concentrated acids?

• A. Add acid to water
• B. Add water to acid
• C. Dilute with lots of water
• D. Keep concentrated acid as is

Answer: (B)

When diluting concentrated acids, the key is controlling the heat released during mixing. The safest approach is to add the acid to a larger volume of water slowly while stirring, so the heat is absorbed gradually and the solution doesn’t spatter. Pouring water into concentrated acid is unsafe because the initial contact can cause rapid boiling and vigorous splattering of acid—localized heat release can shoot acid back out of the container and cause severe burns. The other statements are either describing the safer method in a less strict way or simply not performing any dilution, which keeps the hazard present. So the unsafe practice is adding water to acid.

When diluting concentrated acids, the key is controlling the heat released during mixing. The safest approach is to add the acid to a larger volume of water slowly while stirring, so the heat is absorbed gradually and the solution doesn’t spatter.

Pouring water into concentrated acid is unsafe because the initial contact can cause rapid boiling and vigorous splattering of acid—localized heat release can shoot acid back out of the container and cause severe burns.

The other statements are either describing the safer method in a less strict way or simply not performing any dilution, which keeps the hazard present. So the unsafe practice is adding water to acid.