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2.1 Acids

If you wish to dilute an acid with water before neutralizing it with a base (e.g., sodium hydroxide, potassium hydroxide or sodium bicarbonate), always add acid to water; never add water to acid.

Perform all neutralizations within a fume hood while wearing nitrile rubber gloves, a lab coat, and eye protection.

2.1.1 Hydrochloric Acid

  1. Slowly add hydrochloric acid to a container of cold water to form a 1:10 dilution of acid to water.
  2. Slowly add a 1M potassium hydroxide, sodium hydroxide, or sodium carbonate solution until the pH is in the range of 6.0 to 8.0.
  3. Flush down the drain with an excess of cold water.

2.1.2 Sulfuric Acid

  1. Slowly add sulfuric acid to a container of ice-cold water to form a 1:10 dilution of acid to water.
  2. Slowly add sodium carbonate until the pH is in the range of 6.0 to 8.0.
  3. Flush down the drain with an excess of cold water.

2.1.3 Acetic Acid

  1. Slowly add acetic acid to a container of cold water to form a 1:10 dilution of acid to water.
  2. Slowly add a 1M solution of sodium hydroxide or sodium carbonate until the pH is in the range of 6.0 to 8.0.
  3. Flush down the drain with an excess of cold water.

2.1.4 Phosphoric Acid

  1. Slowly add phosphoric acid to a container of cold water to form a 1:10 dilution of acid to water.
  2. While stirring, slowly add sodium carbonate until the pH is in the range of 6.0 to 8.0.
  3. Flush down the drain with an excess of cold water.

2.2 Bases

2.2.1 Potassium Hydroxide

  1. While stirring, slowly add potassium hydroxide into a container of ice water to form a 1:10 dilution of base to water.
  2. Slowly add 1M hydrochloric acid about 1 ml at a time until the pH is between 6.0 and 8.0.
  3. Flush down the drain with an excess of cold water.

2.2.2 Sodium Hydroxide

  1. While stirring, slowly add sodium hydroxide into a container of ice water to form a 1:10 dilution of base to water.
  2. Slowly add 1M hydrochloric acid about 1 ml at a time until the pH is between 6.0 and 8.0.
  3. Flush down the drain with an excess of cold water.

2.2.3 Calcium Hydroxide

  1. While stirring, slowly add calcium hydroxide into a container of ice water to form a 1:10 dilution of base to water.
  2. Slowly add 1M hydrochloric acid about 1 ml at a time until the pH is between 6.0 and 8.0.
  3. Flush down the drain with an excess of cold water.