Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  • Level: GCSE
  • Subject: Science
  • Document length: 841 words

To determine the value of Faraday constant (quantity of electricity per mole) by using electrolysis of Copper.

Do not show me this again

Are you in the right place?

Jump to Chemistry and see how teachers think you should prepare in:

Extracts from this essay...

Introduction

1) Title: QN1 A Quantitative study of electrolysis 2) Aim/Objective: To determine the value of Faraday constant (quantity of electricity per mole) by using electrolysis of Copper. 3) Results: Before electrolysis: Weight of cathode = 2.164 g Weight of anode = 2.502 g After electrolysis: Weight of cathode = 2.237 g Weight of anode = 2.435 g Time of electrolysis = 20 minutes = 1200 seconds Ammeter reading = 0.19A 4) Calculation/interpretation: The equation of the electrolysis reaction at the cathode: Cu2+(aq.) + 2e- Cu(s.) Gain in weight of cathode = 2.237g - 2.164g = 0.073 g Loss in weight of anode = 2.520 - 2.435g = 0.085 g No. of moles of loss in cupper anode = 0.085 / 63.5 = 0.00134 mol Quantity of electricity required = 0.00134 mol * 2 = 0.00268 mol Quantity of electricity supplied = 1200 * 0.19 = 228C Faraday Constant = quantity of electricity / no.

Middle

ions might not be very soluble at that moment. After that, the copper electrodes were rinsed with propanone and heated under a Bunsen flame. Since propanone can remove grease or oil, this treatment could leash off the sebum which we have left on the electrodes when transferring them. Of course, when rinsing them by propanone, a pairs of forceps was used. After rinsing, the copper electrodes were warmed high on a Bunsen flame to evaporate propanone more quickly. However, they should be placed high above the Bunsen flame because propanone is flammable and a Bunsen flame can oxidize the copper plate, forming copper (II) oxide on their surface, which will finally lead to a heavier weight and smaller Faraday Constant. The value of the Faraday Constant was calculated to be smaller than the literature one (96500 Cmol-1) due to a number of errors. For instance, it was inevitable that the electricity supply was not exactly 0.19A in the time interval 20 minutes.

Conclusion

This can explain why the gain in weight of the cathode and the loss in weight in the anode were not the same. So if the gain in weight of the cathode was taken into consideration, the calculated value of the Faraday Constant would be larger. After finding out the value of the Faraday Constant, the thickness of the metal plating can also be calculated. According to the formulae Density = Mass / Volume and Volume = Thickness * Surface Area, since the density of copper (8920kgm3), the surface area, the mass of copper formed are all known, the thickness of the plating can be known. It is actually calculated by: Mass / Density / Surface area. Such electrolysis process performed in this experiment is useful in electro-plating. It can plate a certain object by placing it on the cathode, and the metal to be plated onto the object will be put on the anode. 6) Conclusion: The Faraday constant was calculated to be 161000 C mol-1. ?? ?? ?? ?? Yu Wing Yee 6A(30) - 1 -

The above preview is unformatted text

Found what you're looking for?

  • Start learning 29% faster today
  • Over 150,000 essays available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Over 180,000 student essays
  • Every subject and level covered
  • Thousands of essays marked by teachers

See related essaysSee related essays

Related GCSE Changing Materials - The Earth and its Atmosphere essays

  1. The Electrolysis Of Copper (ii) Sulphate Solution Using Copper Electrodes

    100 = 2.94% At current intensity 1.09A 0.003/0.108 x 100 = 2.78% At current intensity 1.35A 0.0015/0.134 x 100 = 1.12% Average percentage error = (1.12 + 2.78 + 2.94 + 4.52 + 0.57)/5 = 2.386% In most cases the margin of error is very small and so the graph drawn is precise and the experiment was successful.

  2. Investigate the factors that affect the mass of Copper deposited on the Copper Cathode ...

    After looking at the method and its errors it is then important to assess the reliability of my results in light of all the errors. Despite these errors I acquired a set of results that supported my prediction, particularly evident on the graph showing theoretical values and experimental results.

  1. An experiment to show how electroplating using copper electrodes.

    + 2e- --> Cu(s) According to my results it showed that when the current increases, the mass gained on the cathode also increased. They are directly proportional to each other. The mass gained is directly proportional to the current in the circuit. It is because when the current is 1A, there is one unit of electrons that have been discharged, and become copper cation.

  2. Investigating how the amount of copper affects the mass of the cathode

    * Hair dryer, which will be used to dry the electrodes so that the water of the copper sulphate solution does not get weighed as well as the electrodes leading to an unfair test. * Glass beaker, which will be used to place the copper sulphate solution and the electrodes in.

  1. Investigation into Electrolysis

    concentration of ions in the solution and so thus another reaction will take place instead. Apparatus: Power pack, 2 leads, 1 carbon electrode, 4 Beakers, measuring cylinder, 0.5M solutions of: 20mL Copper II Chloride, 20mL Aluminium Nitrate, 20mL Zinc Sulfate, 20mL Nickel Sulfate and 50mL Potassium Nitrate.

  2. The Electrolysis Of Copper Sulphate Solution Using Copper Electrodes

    The 0.80A anode and cathode variation were also 0.01A. The final reading, 1.00A anode difference was 0.03, and the cathode variation was 0A. This nearly fits the pattern of the greatest variation being at the top, except for the 1.00A cathode variation of 0A. This increasing variation is caused primarily by two things, firstly the temperature of the solution

  • Over 180,000 essays
    written by students
  • Annotated by
    experienced teachers
  • Ideas and feedback to write
    your own great essays

Marked by a teacher

This essay has been marked by one of our great teachers. You can read the full teachers notes when you download the essay.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the essay page.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review under the essay preview on this page.

Do not show me this again

Are you in the right place?

Jump to Chemistry and see how teachers think you should prepare in: