chemical effects of electricity

If we want  to conduct electric current it must contain charged particles to be able to conduct electric current. In solids, the current is carried by means of electrons. Copper, lead, aluminum, iron and carbon are few common examples of solid state conductors. In liquids and gases, the part of a molecule which has acquired an electric charge is a mean of conduction electric current, called ions. These ions may possess either a positive or negative charge, and their examples include the hydrogen ion H+, copper ion Cu++ and hydroxyl ion OH−. Distilled water possesses no ions and is considered as a poor form of conductor of electricity, on the other hand salt-water contains ions and is considerably a good conductor of electricity.

Electrolysis is the process of decomposition of a liquid compound by the way of passing electric current through it. A very useful practical application of electrolysis is the electroplating of metals (see in diagram below). Other examples include refining of copper and the extraction of aluminium from its ore. An electrolyte is a compound which is subject to electrolysis process. Examples include salt water, copper sulphateand sulphuric acid.

The electrodes are the 2 conductors carrying current to the electrolyte. The positive-connected electrode is named as anode and the negative-connected electrode is called the cathode.

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When we place 2 copper wires connected to a battery in a beaker containing a salt water solution, current will flow through the solution. Air bubbles become visible around the wires as the water is changed into hydrogen and oxygen by process of electrolysis.

Electroplating is the technique that makes use of the principle of electrolysis to apply a thin coat of one metal to another metal. We can convert inferior metals to look superior. Few practical applications include the tin-plating of steel, silver-plating of nickel alloys and chromium-plating of steel. If 2 copper electrodes connected to a battery are placed in a beaker containing copper sulphate as the electrolyte it is found that the cathode (i.e. the electrode connected to the negative terminal) gains copper whilst the anode loses all the copper.