physical chemistry experiment
d an research paper on physical chemistry experiment analysis. Needs to be 5 pages. Please no plagiarism.
Need an research paper on physical chemistry experiment analysis. Needs to be 5 pages. Please no plagiarism. Accuracy refers to the degree of technical intimacy between actual measurement and a known standard measurement. On the other hand, precision is concerned with the degree of reproducibility in measurements. Admittedly, both accuracy and precision are key determinants of reliability. In the presence of errors like the inaccurate molarity of NaOH, measurements in subsequent procedures are usually compromised.
This lab report covers the determination of KHP in an unknown through standardization of sodium hydroxide solution using potassium hydrogen phthalate, commonly abbreviated as KHP. NaOH is not only highly hygroscopic but also absorbs carbon dioxide from the air. These properties of NaOH yield substantial errors in the compound’s mass measurements. In practice, the actual concentration of NaOH is determined using KHP as an acidic primary standard (Stanton, 32). The equation for the reaction is KHC8H4O4 + NaOH → NaKC8H4O4 + H2O. KHP has one H+ whereas NaOH has a single OH-. On an ionic basis, H+ in KHP reacts with the OH- in NaOH to form H2O in the ratio 1:1. By titrating a weighted amount of KHP against NaOH, the actual molarity of NaOH can be derived from the resultant titration data. Once the molarity of NaOH has been determined, the percentage, purity of an impure primary standard can be deduced. A suitable indicator, which in this case is phenolphthalein, was used to indicate the titration’s end-point.
Theoretically, standardization of NaOH and determination of a primary standard’s purity are quantitative methods. Therefore, the accuracy of instrument readings is paramount in ensuring the success of volumetric analysis. In this case, the experiment began with the cleaning and calibration of instruments, primarily the burette, mass scales, and Erlenmeyer flasks. Once the instruments were ready, a solution of NaOH was prepared. Procedurally, preparing the solution of NaOH is the first step in determining the actual molarity of NaOH, which will be used in determining the percentage purity of KHP. Slightly concentrated NaOH reacts actively with CO2 to form carbonate ions, a weak base which compromises subsequent steps of a titration experiment (Stanton, 32).