Lab+4+Redox+Titration

Cullen Orengo
 * __Title:__** Lab 4 Analysis by Oxidation-Reduction Titration


 * __Purpose:__** Titration is one of the most common methods for the quantitative analysis of a sample. The purpose of the lab is to learn how to actively use Oxidation-Reduction Titration to make an analysis when necessary. This is done by standardizing a potassium permanganate solution to analyze an unknown iron (II) solution.


 * __Chemical Reaction:__**


 * Teacher Comment: There is a reaction to write for this lab. **
 * __Materials:__** Pipettes, test tube, hot plate, 3M H2SO4, KmnO4(aq), K2C2O4, H3PO4, Iron (II) salt.


 * __Safety:__** Wear safety goggles at all times in lab area, be cautious around hot plates.


 * __Procedure:__** Put 10 ml of Perm, Ox, and Acid into separate appropriately labeled beakers. Place between 1.0 and 1.5 grams of Ox in a clean test tube. Then add an approximately equal volume of Acid to the same test tube. Shortly warm the test tube on the hot plate (Until sides begin to fog up). After this begin to add the Perm from your pipette while swirling around the solution until it remains a constant pink color. Repeat this titration twice more after thoroughly cleaning the test tube used.

Part A

 * =Trial= || 1  ||  2  ||  3  ||
 * Initial mass of Perm pipette || .934g  ||  1.482g  ||  1.489g  ||
 * Final mass of Perm pipette || .665g  ||  1.312g  ||  1.369g  ||
 * ==Mass of Perm== || .269g  ||  .17g  ||  .175g  ||
 * Initial Mass of Ox pipette || 1.047g  ||  1.076g  ||  1.087g  ||
 * Final mass of Ox pipette || .56g  ||  .838g  ||  .91g  ||
 * ==Mass of Ox== || .487g  ||  .238g  ||   ||
 * Part B ||
 * ====Trial==== || 1  ||  2  ||  3  ||
 * Initial mass of Perm pipette || 1.488g  ||  1.406g  ||  1.355g  ||
 * Final mass of Perm pipette || 1.296g  ||  .987g  ||  1.005g  ||
 * Mass of KMnO4 solution used || .192g  ||  .474g  ||  .35g  ||
 * Initial mass of Fe pipette || 1.382g  ||  1.317  ||  1.039g  ||
 * Final mass of Fe pipette || 1.095g  ||  .720g  ||  .581g  ||
 * Mass of iron solution used || .287g  ||  .597g  ||  .458g  ||

1.) This would affect the experiment seeing that iron (III) has a different electron configuration altering the results slightly. The values for iron would come out too high.
 * __Questions:__** ** Analysis **
 * 2.)** This would make the mole ratio of Fe2+ greater than MnO2. This would throw off results because the ratios of Fe2+ are not in proper proportion to MnO2.
 * 3.)** This is a 15% error. This is systematic because it is almost unavoidable and very common.
 * 4.)** 108.9 g, Experimental- 3.01g, Theoretical 55.847g


 * Teacher Comment: Need to see all of the work for this section. The numbers alone mean nothing. **

Pre-Lab
1.) A.) 8H2SO4 + 2KMnO4 + 5K2C2O4 = 2MnSO4 + 10 CO2 + 6 K2SO4 + 8H2O B.) Oxidizing agent – H Reducing agent- K C.)15/26. 3/1 The directions show that the sulfuric acid has a higher mole ratio than potassium permanganate. 3.) 29% Fe A greater mass of water is required to successfully dilute this unknown solution successfully because the density of this unknown solution is much greater than that of water.


 * Teacher Comment: Need a beter conclusion and work for all problems. 35/50 **