Preview

Calorimetry Lab

Powerful Essays
Open Document
Open Document
1598 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Calorimetry Lab
1. Determining the concentration of KMnO4 from the solution created by the stockroom.

16H+ + 2MnO4- (aq) + 5C2O42- (aq) → 2Mn2+ (aq) + 10CO2 (g) + 8H2O (l)

Volume of potassium manganate (KMnO4) = 32.5 mL

Mass of Sodium Oxalate (NaC2O4): 0.104

[KMnO4] Calculation:

= (0.104g of NaC2O4)(1 mol NaC2O4 /134.0g)(2 mol KMnO4 / 5 mol NaC2O4)(1/32.5 mL)(1000 mL /1L)

= 0.00955 M KMnO4

2. Using the standardized concentration of KMnO4 calculated above to find the mass percentage of the oxalate ion

Equation: Volume of KMnO4 reacted with Oxalate ion = (Vol of KMnO4 used in titration - Vol of KMnO4 used in blank titration)

Titration Trial 1

Vf - Vi = VT

54.6 mL -28.1 mL = 26.5 mL

26.5 mL KMnO4 (1 L/ 1000 mL)(0.00955 M KMnO4 / 1L)( 5 mol C2O42-
…show more content…
0.187 mol of K / 0.187 mol of K = (1) x 2 = 2

0.204 mol of Fe / 0.187 mol of K = (1.09) x 2 = 2

0.667 mol of C2O4 / 0.187 mol of K = (3.56) x 2 = 7

1.45 mol of H2O / 0.187 mol of K = (7.75) x 2 = 15

Therefore, the empirical formula for the Iron complex made is K2Fe2(C2O4)7*15H2O

7. Calculating whether or not the net ionic charge of the empirical formula is zero. If not, suggest a new molecule.

(2K)(1+) + (2Fe)(3+) + (7C2O4)(2-) = -6 charge
…show more content…
Another means of modification include using an automatic titration device from Titralabs. The main issue with the volume used for the titrations is that the color change is highly subjective and may change by several mL between partners. These small variations can cause further changes in the calculations later on and could potentially change the results obtained. The automated titration devices use light sensors to notice the change in wavelength in the solution at a given temperature and will thus stop pouring the titrant into the solution when the equivalence point is achieved. In addition, an automated heating chamber could be used to maintain a specific temperature of 80 degrees Celsius when performing titrations because the hot plate will not maintain the temperature of the solution at 80 degrees at all times and therefore may cause you to add more or less volume to the titrated solution. Finally, over the course of the experiment, we noticed different accuracies in the scales we used throughout the lab. The differences between different scales for the same sample go differ by up to 0.100g which could certainly impact the amount of solute we believe we have

You May Also Find These Documents Helpful

  • Satisfactory Essays

    KMnO4 = 5.7E-4 /1mol KMnO4 x 5 moles K2C2O4 /2moles KMnO4 = .001425 moles C2O42-…

    • 315 Words
    • 3 Pages
    Satisfactory Essays
  • Satisfactory Essays

    The mass of an unknown gas is 11.59 g. The mass of an equal volume of He is 1.45 g. Calculate the molar mass of the unknown gas. 32.0 g/mol…

    • 753 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    Molar Conversions

    • 942 Words
    • 4 Pages

    How are we doing? How about the opposite? What if you want to determine the mass of a substance that is represented by moles? Check this video out…………..…

    • 942 Words
    • 4 Pages
    Good Essays
  • Good Essays

    4. A solution is prepared by dissolving 2 g of KCl in 100 g of H2O. In this solution, H2O…

    • 1080 Words
    • 5 Pages
    Good Essays
  • Powerful Essays

    Percent

    • 820 Words
    • 3 Pages

    Objectives: In this Experiment, we will be decomposing KClO3 into two different compounds, KCl and O2. We are given a known mixture that has MnO2 in it to act as a catalyst. When decomposing KClO3 it releases O2 gas, which we then collect into the Erlenmeyer flask. The gas then displaces the water into the beaker, which we can then calculate the water evolved. The first method we use to determine the percent composition is Gravimetric. With this method we use the mass of the reactant and the mass of the product. Another way to acquire the percent composition is by the Volumetric Method. This method requires measuring the water displaced by the O2 gas. If the experiment is done correctly, we should be able to calculate the percent composition of KClO3 by using both methods.…

    • 820 Words
    • 3 Pages
    Powerful Essays
  • Satisfactory Essays

    mole of sodium cyanate (NaCNO) in enough water to make 1.0 liter of solution. [Ka(HCNO) = 2.0 × 10-4]…

    • 4694 Words
    • 42 Pages
    Satisfactory Essays
  • Satisfactory Essays

    K C = [SO 2 ][Cl 2 ] = 0.078 [SO 2 Cl 2 ] 0.078 [SO 2Cl 2 ] (0.078)(0.136) = = 0.15 M [SO 2 ] 0.072…

    • 807 Words
    • 4 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Qualitative Analysis Lab

    • 395 Words
    • 2 Pages

    In the lab, the purpose was to standardize a KMnO4 solution than using it to evaluate how close a H2O2’s concentration was to its labeled concentration. In this lab, it was decided to compare the concentration of new Publix brand hydrogen peroxide to an old sample of the same solution. From the data collected in the first part by titrating a solution of FeSO4*7H2O with the KMnO4 solution, it was determined that the concentration was .028M MnO4-. This was able to be done because a known amount of FeSO4*7H2O was in the solution, from this, when it is completely titrated by the KMnO4 it is possible to find the molarity of the MnO4- used by measuring the amount of it used to titrate the FeSO4. After finding the molarity of the solution it was used to find the percent by mass of H2O2 in the solution.…

    • 395 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    The procedure for the standardization of KMnO4 (aq) was to first fill a clean 50 mL buret with 0.0100 M KMnO4 (aq). Three clean Erlenmeyer flasks needed to be labeled, and a piece of FAS needed to be weighed to 0.5g on a piece of weighing paper. Flask 1 was tarred and tapped into the FAS. The mass was then recorded. This was then repeated with flask 2 and 3. 10 mL of water and 5 mL of 3M H2SO4 was added to the three flasks. 50 mL of water was put in a beaker and 1 drop of permanganate solution was added. The color intensity of the mixture matched the standard and remained for 5 seconds or more. The initial volume was recorded to 0.01 mL.…

    • 1687 Words
    • 7 Pages
    Good Essays
  • Good Essays

    Iodine Clock Rxn Lab

    • 1207 Words
    • 5 Pages

    Purpose: To determine the general rate law for the reaction of S2O82- + I- through a series of experiments and calculations.…

    • 1207 Words
    • 5 Pages
    Good Essays
  • Satisfactory Essays

    Blsj

    • 399 Words
    • 2 Pages

    9.Mn(NO3) 2 + NaBiO3 + HNO3 ( HMnO4 + Bi(NO3) 3 + NaNO3 + H2O…

    • 399 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    3. A chemist dissolves 3.50 g of potassium iodate and 6.23 g of potassium hydroxide in 805.05 g of water. What is the percentage concentration of each solute in the solution?…

    • 255 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Essay on bells

    • 543 Words
    • 3 Pages

    The purpose of this experiment is to standardize a solution of Mohr’s salt, and to use titration to determine the volume ration of ferrous solution to the permanganate standard and calculate the concentration of the ferrous solution. First, Mohr’s salt was mixed with H2SO4. Then, the solution was titrated until the end point was reached. The volumes were recorded, and used to calculate the molarity of the ferrous solution. The major findings in this lab were that titration in a redox reaction can be used to find the concentration of one solution if the other one is given. This lab’s significance is that it shows the proper way to calculate molarities using titrations. The major conclusions show that molarity of an unknown substance can be reached by titrating it with another substance, with a known molarity.…

    • 543 Words
    • 3 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Ch 25 Accounting

    • 12206 Words
    • 69 Pages

    2. 1 K 10. 3 K 18. 4 K 26. 5 K sg34. 4 K…

    • 12206 Words
    • 69 Pages
    Satisfactory Essays
  • Satisfactory Essays

    8/14/2013 Complex Ion Equilibria • The dissociation of complex ions can be represented similarly to equilibria. Simultaneous Equilibria: Solubility Product Constants and Complex Ion Equilibria → Ag + + 2 NH Ag(NH3 ) +2 ← 3 [Ag ][NH ] = [Ag(NH ) ] 2…

    • 294 Words
    • 5 Pages
    Satisfactory Essays