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How to Dissolve Paraformaldehyde

Paraformaldehyde is a white solid formed by the combination of formaldehyde and water. It is similar in its chemical compound to formaldehyde and has essentially the same uses. Paraformaldehyde is used as an embalming agent, a disinfectant against fungi and bacteria and as medicine in wart treatments. When paraformaldehyde is heated with sodium hydroxide, or lye, in a water solution, it depolymerizes or "dissolves" as it reacts to the water molecules. The sodium hydroxide ions act as catalysts to initiate the chemical reaction in the heated solution.

Things You'll Need

Safety mask
Gloves
Distilled water
Beaker
Hotplate
Foil
Dropper
Sodium hydroxide
pH test strips
Concentrated hydrochloric acid
Glass bottles

Instructions

- 1
  Put on a safety mask and gloves. Add 40 grams of paraformaldehyde to 1 liter of distilled water in a beaker and cover the beaker with foil.
- 2
  Heat the solution in the beaker to 60 degrees Celsius over a hotplate.
- 3
  Add about 20 milliliters, or five to 10 drops, of sodium hydroxide to the paraformaldehyde solution immediately after it has reached 60 degrees C.
- 4
  Remove the solution from the heat. Cork and place the beaker in a 70-degree-Celsius water bath. Turn the beaker over a few times at five-minute intervals until the paraformaldehyde has completely dissolved into a clear solution. If it is not fully dissolved, add a little bit more sodium hydroxide.
- 5
  Let the solution cool to room temperature.
- 6
  Check the pH of the solution using a pH test strip. Add concentrated hydrochloric acid to adjust the pH to 7.2.
- 7
  Pour the solution into glass bottles. Adhere formaldehyde caution labels to each bottle. Store in a refrigerator.

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