|MadSci Network: Chemistry|
Gastric acid is an acid solution with a pH of 1 to 2 in the stomach lumen, consisting mainly of hydrochloric acid (HCl)around 0.5%, and large quantities of potassium chloride (KCl) and sodium chloride (NaCl). Generally in the laboratory, HCl is added to water and tested for pH by an electrode or pH paper to achieve a desired pH level or concentration.
If you have access to pH paper, make additions of HCl to a quantity of water and test with the pH paper. This should work well for the experiment.
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