Preparation
22
Hydrochloric acid
When an acid is added to a water sample containing organic matter, the solvent and the
sample separate easily (salting-out effect).
When performing oil content extraction, the salting-out effect can be produced by adding
approx. 6 mol/L hydrochloric acid.
The procedure for preparing 6 mol/L hydrochloric acid using commercially available
concentrated hydrochloric acid (36%) is explained below.
Hydrochloric acid preparation method
Items required
Glass beaker
Glass measuring utensil (measuring flask, measuring cylinder, etc.)
Glass rod
Pure water
Commercially available concentrated hydrochloric acid (36%)
Note
Clean the glass utensils to be used with pure water, and let them air dry completely.
Preparation method
1.
Use a measuring cup to determine a specific volume of pure water and transfer it to
the glass beaker.
2.
Add the same volume (as the pure water) of commercially available hydrochloric
acid, adding gradually by running the hydrochloric acid down the glass rod.
Note
Always add the hydrochloric acid to the pure water. Do not pour in the hydrochloric acid all at once.
Using an incorrect preparation method may cause heat generation and explosive boiling.
