Determination Of The Concentration Of Acid Essay

814 Words Oct 13th, 2015 4 Pages
Determination of the Concentration of Acid in Gastric Juice


Titration is a method where a solution of known concentration is used to find the concentration of an unknown solution. A standard solution is a solution of precisely known concentration. The aim of this experiment was to go over the use of pipettes, burettes, titrations and also to reinforce the concept of molarity.

In this experiment, a titration was carried out using a standard solution of hydrochloric acid to establish the molarity of a solution of sodium hydroxide. The concentration of acid in the gastric juice sample was determined using that solution of sodium hydroxide. The pH of gastric juice was then calculated and compared with the value determined by the pH meter.

Hydrochloric acid reacts with sodium hydroxide to form sodium chloride and water.

HCl + NaOH → NaCl + H2O

Acid- base reactions involve proton transfer. As HCl is a strong acid and NaOH is a strong base they completely dissociate and final product is water.

When the end point was reached, there was a change in colour from colourless to pale pink. This is because the indicator is colourless at acidic pH values and pink and alkaline pH values.

The equation shows a 1:1 ratio. Therefore, the number of moles of HCl equal the number of moles of NaOH.

Gastric acid is produced in the stomach and helps during digestion. One of the main components of gastric acid is hydrochloric acid which has a pH of 1.0. Therefore, it is…

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