QUANTITATIVE DETERMINATION OF TOTAL HARDNESS IN DRINKING WATER BY COMPLEXOMETRIC EDTA TITRATION

CHE 135 Experiment 2, General Chemistry III Lab, Spring Quarter 2015-2016, DePaul University. [Online] htps://www.d2l.depaul.edu (April 19, 2016).

Introduction: The fundamental techniques of organic chemistry lab, commonly known as SIPCAn, include separation, isolation, purification, characterization, and analysis (1). Through SIPCAn, students learn the fundamental techniques of organic chemistry laboratory. Mastering these techniques are necessary in order to perform more complicated experiments and to carry out organic reactions and synthesis. The information gained from SIPCAn included boiling point, melting point, and density can be used to identify unknown compounds. Simple distillation was used to purify a compound by separating it from a

Gilbert, John and Stephen F. Martin. Experiment Organic Chemistry: A Miniscale & Microscale Approach. Belmont, CA: Thomson Brooks/Cole, 2010. 537-547. Print.

The wet, crude product was placed into the 50 mL Erlenmeyer flask. Small amounts of CaCl2 were added to dry the solution. The flask was sealed and the mixture was swirled and left to settle. Once

6. Purpose: to clarify the mechanism for the cycloaddition reaction between benzonitrile oxide and an alkene, and to test the regiochemistry of the reaction between benzonitrile oxide and styrene; to purify the crude product of either trans-stilbene, cis-stilbene, or styrene reaction.

For the cation analysis, 0.566 g of an unknown compound was dissolved completely in 5mL of distilled water in a centrifuge tube, thus confirming this solution as a stock solution. A flame test was performed on the stock solution to give a general idea of what test was to e preformed on the stock solution deriving the information from our logic trees in part 1. The logic tree from part 1 and the flame test confirmed that we needed to conduct an ammonia test on the stock solution. To being the ammonia test, 15 M NH4OH was added drop wise (about 20 drops) to the stock and the color of the solution and the color of the solution was recorded. 10 more drops of 15 M NH4OH

The purpose of this experiment was to determine the molar solubility, the solubility constant, and the effect of a common ion on the molar solubility of calcium hydroxide. To accomplish this the experiment was split into two parts; part A and Part B. in Part A of the experiment a standardized 0.05 M solution of HCl was titrated into a 25 mL solution of saturated Ca(OH)2 which contained 2 drops of orange methyl identifier. Once the titration began, the HCl was added until the methyl orange endpoint was reached, and as a result the volume of the HCl needed for the endpoint to be reached could be used in

Procedure: Refer to pages 67-76 of General Chemistry 1210: General Chemistry Laboratory Manual by the Department of Chemistry, The Ohio State University, Hayden-McNeil Publishing, 2016.

Fifield, F. W. and Kealey, D. 1995. Principles and Practice of Analytical chemistry. (4th ed) Glasgow, Blackie Academic and professional.

CHE 133 Experiment 3, General Chemistry II Lab, Spring Quarter 2014-2015, DePaul University. [Online] https://www.d2l.depaul.edu (accessed April 25, 2015)

The light yellow precipitate was collected by suction filtration using a Hirsch funnel. The product was washed with two 1-mL portions of cold methanol followed by two 1-mL portions of diethyl ether. The product was dried in the oven at 110°C. The IR spectrum as a KBr pellet was obtained for the product and inosine for analysis.

Koczanski, Krystyna; Xidos, James D. CHEM 1300 Laboratory Manual; UMSU Copy Centre: Winnipeg, MB, Canada, 2013, pp

This process was then repeated two more times with subsequent additions of 10 mL of the 0.5M aqueous NaHCO3 and the aqueous layers drained off into the above mention labeled 100-mL beaker. Finally 5 mL of deionized water was placed into the funnel and mixed. The water was then drained off into the beaker containing the aqueous solution extracts. The solution was then saved until need later in the experiment.

In this experiment, the Ksp for calcium sulfate dihydrate, CaSO4·2H2O, by titrating 4 times a calcium sulfate dihydrate solution with diprotic EDTA, H2(EDTA)2-. For each trial we found the Ksp by means of molarities and activities. The results for the Ksp using only molarities was very different than the Ksp using activities. The average Ksp using molarity only was 2.26 x 10-4 and the average Ksp using activity turned out to be 2.31 x 10-5. The actual Ksp however, is 3.14 x 10-5. A percent error of 26.6 % was calculated.

Sodium hydrogen carbonate was added to the solution until it becomes neutral. Ph paper was used for this test to determine its ph value.