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

Electrochemistry and electrolysis.

Extracts from this document...

Introduction

Electrochemistry USING an electric current to produce chemical changes is called electrolysis. It is often used to purify metals and other substances. An electric circuit is set up using two electrodes, an electrolyte (a liquid containing ions), and a source of electricity. When the electricity is on, ions in the electrolyte move towards the electrodes. There, they gain or lose electrons, making them - and the electrodes - chemically different. Chemical changes can also produce electricity. A battery consists of an electrolyte between two different metal electrodes. Chemical reactions occur between the electrodes and the ions in the electrolyte, making electrons flow. PURIFYING COPPER If a current is passed through copper sulphate solution, positive copper ions move from the impure copper anode to the cathode, where they are deposited as pure copper metal. ...read more.

Middle

metal The element copper is a lustrous reddish-brown transition metal. It is malleable and ductile, and is a good conductor of electricity. It was first used about 5,000 years ago in the form of bronze (an alloy of copper and tin) to make tools, but was later replaced by iron. It has also been used in coins, and today is used in electrical cables, wires, and other components, and also in plumbing. Properties and Uses The reddish-brown colour of copper is due to a thin film of oxide, and when the film is removed the colour of the pure metal is rosy pink. It is an extremely tough metal, and can be drawn out into a thin wire or hammered into a thin leaf. ...read more.

Conclusion

It may be combined with a number of other metals to make a wide range of useful alloys. Electrolysis This method is sometimes used for extracting copper from the ore, but is usually employed as a means of refining the already purified metal. Commercial copper refined in this way is one of the purest commercial metals, with a purity of about 99.9 per cent. Ingots of the unrefined metal are placed in copper sulphate, and these form the anodes, while sheets of pure copper function as cathodes. As a current is passed through the solution, the anode is eaten away and pure copper is deposited at the cathodes. The impurities pass into solution, unless they are silver and gold, which settle as slime on the bottom of the tank and can be recovered. ...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

    What is a metal ore?

    4 star(s)

    Iron from a blast furnace is called pig iron and contains many impurities such as high levels of carbon. If this iron is melted and allowed to cool under careful conditions we get cast iron, which can be used, for objects such as guttering.

  2. GCSE Physics Resistance of a Wire

    For the temperature of the wire I would not be able to carry out a fair test because it is extremely difficult to produce and control the range of temperatures needed without the correct equipment. If I chose to measure the difference in the resistance in different materials I would

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

    The experiment was inaccurate in the following ways. It was very difficult to know to what extent to clean the copper cathode, to ensure that the cathodes were in equal conditions in each experiment to allow new copper to stick to old copper. Also the electronic balance only gave masses to two decimal places, so the masses recorded may not have been as accurate as they could be.

  2. Electrolysis of Copper Chloride

    At 0.5 molar 0.23 grams of Copper is produced. 0.23 grams is nearly the exact double of 0.11 grams. This proves the prediction that the higher the concentration, the higher the amount of Copper produced. The actual results produce a graph with positive correlation, though there was seemingly one problem in the graph.

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

    The ionic half equations in this experiment are:Cu(s) - 2electrons --> Cu2+ (aq) Cu2+ + 2electrons --> Cu One Cu atom is turned into Cu2+ at the anode which then discharges at the cathode to become Cu yet again. So one Cu atom is lost at the anode and gained

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

    Therefore, positive copper ions are released from the anode into the copper sulphate solution. In effect, the copper anode is constantly supplying the electrolyte with copper which is then in turn discharged and deposited at the cathode. This means that electrolysis will not cease until the copper anode immersed in

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

    solution may loose or gain electrons and are changed into neutral atoms. The reaction at the electrode depends on the voltage that is applied. Here is an example of what I expect to happen in this experiment. When the solution of copper sulphate has dissolved in water, it divides into positive copper ions and negative sulphate ions.

  2. Making an electric cell

    Going back to the magnesium and copper equilibria: All we need to know is that the magnesium equilibrium lies further to the left than the copper one. We need to know that magnesium sheds electrons and forms ions more readily than copper does.

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