In this lab we will use basic titrating skills and techniques in order to titrate HCl. We will also be practicing how to prepare the solution. Using the titration data, we can practice our stoichiometric skills and also become more familiar with using lab equipment. Titration is the process of measuring the exact volume of a solution of known concentration that is required to react completely with a measured volume of a solution of unknown concentration or a known mass of unknown solid. A solution of accurately known concentration is called a standard solution. To be considered standard, the concentration of the solute in the solution must be known to four significant figures. When an acid or base solution is prepared from stock acid or base, the concentration is approximately known. However, due to relative purity and limitations on the accuracy and precision of measuring quantities for solution preparation, the solution’s exact concentration is not known. For this reason, the process of standardization is used. Standardization is a laboratory process in which the exact concentration of a solution is obtained by comparing the concentration of the solution to a primary standard, a dry substance of known purity.
Part A - Preparation of 0.1 M HC1 Solution
1. Prepare 250m1 0.1 M HCl solution from the 6 M stock solution provided. Calculation: (6 M) (?ml) = (0.1 M) (250 ml)
2. Prepare the solution by adding approximately l00ml distilled water to the 250 ml volumetric flask, pipetting the calculated volume of stock 6 M HC1 solution into the flask, and diluting to the mark with distilled water. Apply parafilm to the flask top and invert and shake to assure mixing.
Part B - Standardization of HC1 Solution
1. Clean and Dry three 125ml Erlenmeyer flasks.
2. Mass three portions of...
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