In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water. The absorption spectrum for varying concentrations of Fe2+ are measured using a spectrophotometer and the data is graphed in Excel. The slope of the line is ε in the Beer-Lambart equation A = εcl. In the second part of the experiment, eleven flasks containing diluted stock solutions of Fe2+ and ligand are mixed with 5 mL 2 M sodium acetate and 4 mL 3 M NH2OH and diluted with water. The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel.
Fill the burette with 0.005mol dm-3 potassium manganate(VII) solution. 6. Pour some of the thyme extract solution into a 250cm3 plastic beaker. 7. Using a measuring cylinder, add 50cm3 of 1.0mol dm-3 sulphuric(VI) acid to the thyme extract in the conical flask.
6. How many moles of NaCl are in 250. mL of a 0.200 M solution? 1. 15.8 g of KCl is dissolved in 225 mL of water. Calculate the molarity.
What volume of 2.0 M hydrochloric acid is needed to completely react with the amount of calcium carbonate in Part 2a above? c. Based on Parts 2a and 2b above, how many moles of water would be produced? 3. Ammonium chloride and calcium hydroxide react according to the following balanced equation: 2 NH4Cl(aq) + Ca(OH)2(aq) ⋄ CaCl2(aq) + 2 NH3(g) + 2 H2O(l) a. What mass of ammonium chloride is needed to make 3.0 liters of a 1.5 M ammonium chloride solution?
0.00512 * 500 = 2.56 c. 0.00806 * 319.9= 2.56 d. 0.00806 * 319.9 = 2.56 500 mL =0.5 L e. 0.0161 * 500 / 2 =2.56 4. Exercise 4: a. 0.250M; 250 mL 0.25 L (0.25) (0.25) = 0.0625 moles ZnI2 b. Prepare the solution by dissolving 19.95 grams of Zinc Iodide with 250 mL of water. c. Prepare the solution by dissolving 38.90 grams of ZnI2 with 500 mL of water.
Abstract The focus of this experiment was to analyze the kinetics of a nucleophilic substitution. A mixture of 0.3622-M 1-bromopropane and 0.3622-M potassium hydroxide in an 90:10 ethanol/water solvent provided the reactants for a SN2 reaction to occur in a temperature controlled bath at 50.0˚C. The disappearing reactant was found by titrating timed aliquots during the reaction and then measuring the concentration of hydroxide. The k-value was found to be 0.0202 M-1Min-1. Using the linear form of the Arrhenius equation the activation energy was calculated to be 19.9 kcal/mol.
For zinc ion to react, the NaEDTA must also be an ion in the solution which means that the large salt must be dissolved in water. Procedure 1) Weighed out 3.64 of NaEDTA on an electronic beam balance 2) Added this mass of NaEDTA using wide mouth funnel to a 250 mL volumetric flask. 3) Rinsed the funnel with a squirt bottle containing deionized water making sure none of the solid remained in the funnel. 4) Added about 100-200 mL of deionized water to the volumetric flask containing the solid NaEDTA. 5) Swirled the solution until the NaEDTA (s) dissolved entirely.
Calculate the Normality of the vinegar using the previously given equation. Na = (Nb)(Volumeb) (Volumea) C. Calculate the mass of the acetic acid in grams using the previously given equation. Massa = (Na)(GMWa) D. Calculate the percentage of acetic acid using the previously given equation. % Acid = Massa(g/L) x 100 1000g/L Discussion and Conclusion: Questions: LabPaq question guidelines: Answer questions A and G in the lab manual. Skip questions B, C, D, E and F in the lab manual, and answer these instead: A.
The following data were obtained when a sample of barium chloride hydrate was analyzed as described in the Procedure section. Calculate (a) the mass of the hydrate, (b) the mass of water lost during heating, and (c) the percent water in the hydrate. Mass of empty test tube 18.42 g Mass of test tube and hydrate (before heating) 20.75 g Mass of test tube and anhydrous salt (after heating) 20.41 g. Mass of the Hydrate is 2.33g. Loss (H2O) is 0.34g. Percent H2O in Hydrate is equal 0.34/2.33=14.6% 3.
CHEM 1412 SAMPLE FINAL EXAM PART I - Multiple Choice (2 points each) _____ 1. In which colligative property(ies) does the value decrease as more solute is added? A. boiling point B. freezing point and osmotic pressure C. vapor pressure D. freezing point and vapor pressure _____ 2. What is the molarity of a solution prepared by dissolving 25.2 g of CaCO3 in 600 mL of solution? A.