• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11

The aim of this experiment is to discover how the rate of electrolysis is affected by the level of voltage.

Extracts from this document...


Aim The aim of this experiment is to discover how the rate of electrolysis is affected by the level of voltage. Possible Variables * Size of electrodes * Level of voltage * Time * Distance between electrodes * Molarity/Concentration of Electrolyte * Temperature of Electrolyte Plan As a group we have decided that our variable will be the level of voltage. We came to this decision because it will give us accurate results and a good range. For our experiment, we shall use the following pieces of equipment and apparatus: * 1 Power pack with adjustable voltage * 2 wires * 1 beaker * Copper sulphate solution (CuSO4(aq)) * 2 copper electrodes of equal weight (Cu(s)) * 2 crocodile clips * Top pan balance * Stop Watch (to time 5 minutes) Diagram Firstly we shall weigh each copper electrode and record their weights. Secondly, we shall set up our equipment as shown in the diagram. We shall then turn on the power pack, and wait for five minutes and then turn the power pack off. The electrodes will then be weighed again and the new weights recorded. We shall then repeat this process using a higher voltage. The voltages we shall use are 2, 4, 6, 8 and 10 volts. ...read more.


to form cations in the solution which are then attracted to the cathode as detailed above. 2) Therefore the mass of copper gained by the cathode exactly equals that lost by the anode. 3) Electrolysis occurs at a faster rate when a greater voltage is passed through the electrolyte because, if there is a higher voltage that means that electrons are passing through the circuit at a greater speed, so electrolysis reaction can occur faster and the whole process is speeded up. Method Our experiment went ahead as detailed in my plan. Results Table 1 Voltage (v) Cathode's weight after 5 minutes of electrolysis (grams) Anode's weight after 5 minutes of electrolysis (grams) 0 1.5 1.5 2 1.59 1.43 4 1.70 1.34 6 1.85 1.16 8 2.10 0.90 10 2.52 0.51 Results Table 2 Voltage (v) Cathode's weight after 5 minutes of electrolysis (grams) Anode's weight after 5 minutes of electrolysis (grams) 0 1.5 1.5 2 1.57 1.42 4 1.69 1.33 6 1.84 1.15 8 2.08 0.93 10 2.52 0.48 1st Results 2nd Results Voltage (v) Cathode's average weight after 5 minutes of electrolysis (grams) Anode's average weight after 5 minutes of electrolysis (grams) 0 1.5 1.5 2 1.58 1.425 4 1.695 1.335 6 1.845 1.155 8 2.09 0.915 10 2.505 0.49 Results Table 3 Results Table 4 Voltage (v) ...read more.


It is likely that the copper used in our experiment was not pure and therefore this would account for the very slight anomalies in the results. (i.e. direct proportion was approximate) * Another factor which may have affected the overall outcome of the investigation may have been the fact that the practical work of the investigation was carried over from lesson to lesson, meaning that variables such as the concentration or the amount of the Copper Sulphate solution could have changed between lessons. To overcome this problem, a stock solution of Copper Sulphate should have been made so as the concentration remained the same at all times. The same electrodes and equipment should have been used throughout. Also, when weighing, the same electrical balance should have been used as there may have been slight differences between the two balances. This is what could explain the slight anomalies in the graph. Despite the fact that my results seem to be quite conclusive, there is not enough evidence to prove my predictions are absolutely plausible. For this to be possible, one would need to repeat the experiment hundreds of times. It would also be necessary for other people to carry out the experiment and achieve the same pattern of results. I did not find any major anomalies in my results; this can be seen by the uniformity of my graph lines. Alastair Bealby Chemistry Coursework Page 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Changing Materials - The Earth and its Atmosphere section.

Found what you're looking for?

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

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Changing Materials - The Earth and its Atmosphere essays

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

    During the experiment the current seemed to be fluctuating quite frequently, especially when using higher currents and although most times the current was adjusted back to its previous amount using the ammeter as soon as possible, at times the experiment was left unattended for a minute or two and the current could have fluctuated then.

  2. What Effects the Reaction in the Electrolysis of Copper Sulphate.

    0.86 0.79 1.14 1.21 3 0.86 0.79 1.16 1.23 300 1 0.81 0.72 1.21 1.26 ** 0.09 2 0.79 0.70 1.21 1.30 3 0.79 0.71 1.23 1.31 350 1 0.72 0.62 1.26 1.36 0.11 2 0.70 0.60 1.30 1.40 3 0.71 0.59 1.31 1.43 400 1 0.62 0.50 1.36 1.48

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

    Since the temperature increases were very small at this amperage I tried at a slightly higher one. At 0.3A two experiments were carried out after two and five minutes because ten minutes was too long: Time (min) 2 5 Temperature increase (0C)

  2. Investigation to show how the amount of electric current affects the amount of copper ...

    is directly proportional to the electric current. Below is a line graph showing the average change in mass of the anode: As can be seen, the line of best fit in the graph above does not go through all the points. As a matter of fact it goes through all the points except for the first one

  1. In this coursework, I aim to find out the different properties of gold and ...

    less chance that they would be bias towards 24 carat gold, which would make my data more accurate, reliable and valid. Furthermore, I could have also analysed a few other factors of alloys, such as their electrical conductivity, thermal conductivity, or I could even have looked at which alloy is more popular.

  2. Investigate how the rate of electrolysis is affected when changing the current in the ...

    When they are in liquid form the ions are free to move around. This enables them to conduct electricity and to move towards the electrodes. Metal ions are positive and non-metal ions are negative. We know that opposite charges attract, there fore the metal ions would be attracted to the

  1. Quantitative electrolysis concerns the amount of product obtained in an electrolysis, and the various ...

    ? Cu2+(aq) +2e- At the Cathode: Cu2+(aq) + 2e- ? Cu(s) Anode Cathode Copper is lower down in the reactivity series, But copper from the electrode is deposited away from the anode to form at the cathode instead of CuSO4 splitting into ions themselves. Collision Theory In order for reactant molecules to react with each other, they must firstly collide with each other.

  2. OCR Coursework Investigation

    I will repeat each concentration three times to make sure my results are reliable. Table of Results Volume of sodium thiosulphate Volume of water Time taken for X to disappear (seconds) % Cm3 % Cm3 1 2 3 Average 60 60 40 40 68 57 65 63 70 70 30

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work