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Acids And Bases: Determining Equivalence Point And Molar

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Acids And Bases: Determining Equivalence Point And Molar
Lab S: Acids and Bases: Titrations | Determining Equivalence Point and Molarity
Susheel Palakurthi
11661148
Partners: Justin Mwakule, Andrew Farrell
July 29, 2015
CHEM 123 L02
TA: Amelia Fitzsimmons
Experiment conducted: July 22, 2015 Introduction
Acids and bases is an important aspect in chemistry. A specific example of such is in the body, acids and bases have to be balanced in order to provide the optimal pH in the system for normal physiological processes. Anything digested by the body has the ability to change the body’s standard (or current) pH. A pH of the body which is too acidic or too basic can lead to problems with one’s health1. An example of acid excess is hydrochloric acid in the stomach, causing someone to have acid reflux …show more content…
The purpose of titrating is to measure the unknown amount of a substance in a sample through the chemical reaction with a known amount of suitable reagent4.
The pH scale is a measure of acidity or basicity of a solution or substance by the measure of hydrogen ion concentration, and ranges from 0 to 14. The number 7 on the pH scale is the neutral value which usually represents water. Numbers above 7 represent bases while the numbers below 7 represent acids. In this experiment, there were two methods of determining the pH of a reaction: using a pH meter and an indicator. An indicator is a weak acid or base and reacts with the reactants and produce different colors in order to show the pH level. A reaction equation of such is:
HIn+OH^-⇌ H_2 O+In^- (2)
(In = indicator dissociation …show more content…
With the use of the equation pH= -log⁡[H_3 O^+], the equivalence points of the pH for hydrochloric acid and acetic acid can be concluded. As sodium hydroxide is added to the beaker, the concentration of hydronium decreases, which in turn causes the pH to increase, thus follows the equation. This information, combined with the volume of the titrant and the molarity of the titrant can be used to determine the stoichiometric factors for the following equation, for the acetic
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