A.G.R. SUAREZ
INSTITUTE OF BIOLOGY, COLLEGE OF SCIENCE
UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY 1101, PHILIPPINES
DATE SUBMITTED: 5 DECEMBER 2012
DATE PERFORMED: 23 NOVEMBER 2012
INTRODUCTION
All chemists must know how to prepare solutions of varying concentrations because many reactions in quantitative analysis take place in an aqueous medium. In this experiment, solutions were made using 2 methods.
The first method used was dissolution. A specific mass of solid was dissolved in a specific volume of distilled water.
The second method was dilution. A specific volume of a certain concentration was added to distilled water until the desired concentration was obtained.
Once the standard solutions have been prepared, they were standardized. Standardization involves preparing a solution using the primary standard and titrating it with the titrant to the endpoint to be able to calculate the exact concentration of the primary standard.
PROCEDURE OF THE EXPERIMENT
There are four parts to this experiment, two of which involve preparation with the remaining to involving standardization.
The first part was the preparation of 250ml of 1.0 M sodium hydroxide (NaOH) solution from a solid. Using a top-loading balance, ____ g of NaOH was transferred to a clean Erlenmeyer flask. Distilled water was then added until the solid was completely dissolved. The solution was transferred to a 250ml volumetric flask and mixed.
Once mixed, the solution was bulked to the mark and mixed again. Finally, the solution was transferred to a clean plastic bottle and labeled.
The second part was the preparation of ml 100ml of 3.0 M hydrochloric acid (HCl) solution from a more concentrated (12.1 M) HCl solution. Using a pipette, ____ ml of concentrated HCl was transferred to a clean Erlenmeyer flask that already contained around 25ml distilled water. Distilled water was then added until the solution
References: VAuthor. Chemistry. Belmont, CA: Thomson Brooks/Cole, 2007. Skoog, West, Holler. 1992. Fundamentals of Analytical Chemistry. 6th Edition Brown, Le May, Bursten. 2002. Chemistry: The Central Science. 8th Edition. Whitten, Davies, Peck, and Stanley, 2007.Chemistry.8th Edition. Institute of Chemistry.Analytical Chemistry Laboratory Manual. 2009. Quezon City: University of the Philippines, Diliman. International Union of Pure and Applied Chemistry. (2008, June). General principles and terms of titration processes. Retrieved on 04 December 2012 from http://old.iupac.org/publications/analytical_compendium/Cha06sec2.pdf