• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Does the Magnitude of current affect the rate of electrolysis?

Extracts from this document...


Does the Magnitude of current affect the rate of electrolysis? Plan The circuit that I shall use in this experiment will be built as the diagram shows. During electrolysis the copper electrodes either receive from, or donate to, copper ions infrom the copper sulphate electrolyte solution. If the electrolysis is affected by the magnitude of the current flowing this could be demonstrateden by measuring the current and weighing the electrodes before and after a fixed period of time. The positive ions of copper in solution will deposit at the negative cathode which will therefore gain in weight whilst the positive anode will release copper ions into the electrolyte and so lose weight. Method With the power on I shall adjust the variable resistor to give the exact current flow required (I can do this by observing and recording the ammeter reading). The current flows that I will need set in(on different experiments) are: * 0.10A * 0.15A * 0.20A * 0.25A * 0.30A The circuit will then be left for a measured ten minutes (on every test)at each current setting. Before and after every experiment both the electrodes will be weighed. The weighing of electrodes allows us to: a) See Confirm whetherif electrolysis has taken place. b) Measure the rate of electrolysis in Copper Sulphate and therefore we will be able to deduce whether a higher current affects the rate of electrolysis. ...read more.


* If current had nothing to do with the rate of electrolysis, there would not be power plants situated next to every place where this process is carried out industrially. * Increasing the current requires more ions in solution to deposit their charge at the electrodes. The more ions reaching the electrode the more copper is deposited/released * As the weight gain/loss at the electrodes should be proportional then the weight deposited per unit current should be a constant Results The results of the average weight gains/losses at electrodes for each experiment have been recorded in Table 1. The average weight gain/loss (g) for each current level has been calculated. The average weight change per unit current has also been calculated (mg/amp) Table 1 Average weight gain/loss at electrodes + - + - + Amps (A) WEIGHT (g) Mg/amp-0.03 +0.05 -0.06 +0.04 -0.05 Electrode +/- Before After DifferenceAfter Average changeDifference +0.01 -0.01 +0.04 -0.04 +0.04 - 0.10 0.84 0.85 +0.010.85 0.01 100 + 0.10 0.88 0.87 -0.010.87 - 0.10 0.850.62 0.86 +0.01 + 0.10 0.870.62 0.86 -0.010.58 - 0.15 0.620.87 0.66 +0.040.91 0.04 267 + 0.15 0.620.85 0.58 -0.040.82 - 0.15 0.661.12 0.70 +0.031.17 + 0.15 0.580.98 0.54 -0.050.92 - 0.20 0.870.94 0.91 +0.040.98 0.035 175 + 0.20 0.850.75 0.82 -0.030.70 - 0.20 0.91 0.94 +0.03 + 0.20 0.82 0.78 -0.04 - 0.25 1.12 1.17 +0.05 0.055 220 + 0.25 0.98 0.92 -0.06 - 0.25 1.17 1.23 +0.06 + 0.25 0.92 0.87 -0.05 ...read more.


* Not drying the electrodes properly (increased weight - water) * The balance did not have sufficient accuracy for the measured weight range Possible alterations The experiments could be further improved and standardised to remove variables and improve accuracy as follows: 1. The experiments could be repeated more times, and therefore gaining a higher degree of accuracy in the average weight gain/loss. . 2. Instruments and balances of greater accuracy could be used 3. By introducing an evaporation drying process we could remove a major variable of level of drying the electrodes. I consider this the possibly greatest variable in the experiment 4. By using a constant area and weight electrodes set at constant separation which would create the same conditions at each electrode between experiments. These would change during electrolysis and if different to start with could possibly affect the accuracy of measurements when comparing one experiment with another. 5. Using a fresh amount of electrolyte for each experiment would ensure the same starting conditions in solution Viewpoints of my experiment I could also: * Test this experiment using other solutions and electrode materials. * Test for the effects of a voltage increase. * Run this same experiment over a split longer period of time, (weighing each electrode in each interval, before continuing the test. )This would show if the electrolysis rate would remains constant throughout the electrolysis period. * Repeat the tests at higher temperature of electrolyte Nathan Hart Science Coursework Page 1 of 5 07 May 2007 ...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. Peer reviewed

    To find out how current affects the rate of electrolysis

    3 star(s)

    factors in the ionic equation of reaction, so it should not have an effect. However, at very low concentration, the resistivity of water increases due to the lack of dissolved ions, and this would have an effect on the current and therefore having an effect on the mass of copper deposited.

  2. Investigate whether changing voltage will affect the rate of Electrolysis.

    Crocodile Clips Stop Watch Glass Beaker Balance = used to weigh graphite rod After collecting our equipment and setting up our apparatus, we poured into the glass beaker 200mm of Copper Sulphate. We set the power pack on 2 volts and waited for 5 minutes, to see whether a reaction had occurred or not.

  1. Investigate whether voltage affects the rate of electrolysis?

    I may have anomalous result in my result for 12 volts of current because there is a huge leap from the result for 10 volts to the result for 12 volts, which seems irregular but I have still decided to keep it in my graphs and results just to show

  2. How does concentration affect the rate of electrolysis of Copper Sulphate solution?

    Then copper is produced at the cathode meaning that the ions have successfully transferred and now have a full outer shell of electrons. As the concentration of the solution increases, so do the ions within the solution. This means that more and more copper ions are moving around within the

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

    Another result which was quite a long way from the predicted theoretical value and could be called anomalous was the 1st result using the current 1A, where a mass of 0.44g was deposited on the cathode. This second result did not appear an inconsistent result at first but when the

  2. Importance of electrolysis in our daily lives

    o Firms should avoid using broken or cracked racks o Proper control of bath operating parameters can result in more consistent work piece quality o Facilities should perform daily or weekly tests and analysis for proper inspection.

  1. Electrolysis: How Does Current Affect The

    ion, 2 electrons are needed to become copper metal. Therefore two moles of electrons are needed to liberate 1 mole of copper ion, giving one mole of copper metal. The current measures how many electrons flow through the circuit in a set time, so if the time is constant the only factor which will affect the mass of copper

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

    + 2e- ==> Cu(s) I believe that my experiment was fairly accurate. My method was good enough to get good results. In particular my way of removing excess materials from the copper electrodes was very good. I also believe I planned my experiment out to be quite fair as stated when I gave reasons why this is a fair test.

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