Titration Essay

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Titration is a technological process in which a solution, known as a titrant, is slowly and carefully added from a burrette into a fixed volume of another solution (known as the sample). In an acid-base titration an acid neutralizes a base or vice versa. This process is maintained untill the reaction between the titrant and the sample (acid and the base) is judged to be complete. The reaction is judged to be complete when the endpoint is reached. An endpoint in a titration analysis is referred to as the point at which no more titrant is added due to an observable colour change of an indicator. Indicators can be used to find an endpoint because they change colour when the pH of a solution changes and an endpoint in a titration is an empirical approximation of the equivalence point, which is the point of major pH change in the titration sample due to the fact that equal chemical amounts of reactants have been combined at that point. All indicators have a pH range, which is the range of pH values at which the colour of the indicator changes. Thus…show more content…
A polyprotic acid is a substance that can give more than one proton (hydrogen ion) and a polyprotic base is a substance that can gain more than one proton (hydrogen ion). However, through evidence of titration graphs involving polyprotic acids or bases it can be seen that a polyprotic substance does not give or take more than one proton at once rather it gains/loses one proton at a time. Meaning that if a polyprotic acid loses two protons it loses them through two reactions, each involving a single proton transfer. Since polyprotic substances undergo more than one proton transfer reaction, they have two equivalence points and thus two curves on their titration graphs. Take the example of a polyprotic acid, such as H2SO3, if it were to be titrated with a strong base, its graph would look something like
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