Experiment on Titrimetry

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In this experiment we are trying to identify an unknown acid or base and its concentration by using the method of titration. The pKa values and the titration curve help aid in identifying of the unknown. In our case we had a base as our unknown (analyte). The use of a certain amount of sodium hydroxide and hydrochloric acid will be used to titrate the unknown solution that is given. This is the tirant. We used hydrochloric acid as our titrant. We achieved a pH of 5.56 at an end point of 10 milliliters. The unknown’s concentration was around 0.098 M at pka(s) of 6 and 7. The sodium hydroxide and hydrochloric acid are called titrant and it is contained in a container called burette. The unknown solution is held in an erlenmeyer flask. The purpose of the experiment is to measure the weak acid and base by neutrilizing it and determining the unknown acid by titration.

Introduction: Titration is a common laboratory practices that is involved in quantitative chemical analysis. This process is also called titrimetry or volumetric analysis (since we are dealing with volumes in our analysis). This process is used is used to determine unknown concentration of a solution. This is unknown solution is known as the analyte. The standard solution or known concentrations is called titrant. The titrant and analyte react to determine an accurate concentration of the unknown solution. This is the process that happens in titration. There are many types of titrations like acid-base titrations, redox titration, and gas phase titration, but the most commonly used titration is acid base titration. An acid base titration is used when an acid or base concentration needs to be known (for example this lab is an acid base titration). In the process of acid- ...

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... For example, when weighing out the amount of HCL and NaOH needed for the standard solutions, the last decimal point on the mass number on the scale would be shifting. So this causes an uncertainty. This is another type error caused by instruments. The pipets for example wouldn’t be able to take in the right amount of solution because the edge is chipped or cracked. Also, if one did not calibrate the pH meter by Scholar 425. The value they receive would be an error. Also dirty burets that have impurities with chemicals or water would affect the concentration of solution. If this happens the molarity will be wrong and the volume would have been read wrongly. Overshooting the endpoint is another error this will give a steep rising curve and a drastic change in the pH. To deal with the change in pH more titrant will be used and thus affecting the volume and molarity.

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