How to Neutralize HCL
- 1). Energize the exhaust fan or fume hood and ensure it is operating correctly. Check this by placing a small piece of tissue paper near the inlet of the exhaust fan or just outside of the fume hood. The tissue should move toward the inlet of the exhaust fan or into the fume hood.
- 2). Don the rubber apron, protective goggles and PVC gloves. Place the containers with the HCL and NaOH, glass beaker, jar with lid, glass funnel, pH paper and stirring rod into the work area, which should be directly under the exhaust fan or inside of the fume hood.
- 3). Separate the containers of HCL and NaOH and place the glass beaker in between them. Pour HCL slowly into the beaker until it is approximately one-third full. Grasp the container of NaOH and slowly add several drops, one at a time, to the beaker of HCL. Because the NaOH is a base, and acids and bases react violently, steam and heat will be created. Do not rush this step.
- 4). Stir the solution with the stirring rod to thoroughly mix. Continue adding NaOH slowly and mixing it with the stirring rod until the reaction slows. Remove one pH paper strip and dip the end of it into the solution. Compare the color of the wet portion of the strip to the color chart on the pH paper container. Continue adding NaOH until the pH paper indicates that the pH has reached 7.5, which indicates that the HCL is now in a neutral state.
- 5). Remove the lid from the glass jar and insert the glass funnel into the opening. Slowly pour the neutralized HCL into the glass jar and recap. Recap the HCL and NaOH containers, and ensure there is no spillage on them, the jar, or in the work area, and remove the items from the work area. If necessary, clean the work area and then remove the goggles, gloves and apron.
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