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Chemical effects of Electric Current

Electroplating, Key Terms and Facts, Chemical effects of Electric Current etc.

Chemical reactions are caused by the electric current passing through the conducting solution. This is called the chemical effects of currents such as:

  • Formation of gas bubbles on the electrodes
  • Deposition of metal on electrodes
  • Change of colour of solutions

In 1800, a British scientist, William Nicholson (1753–1815), had shown that assuming terminals were submerged in water, and a current was passed, air pockets of oxygen and hydrogen were created. Oxygen bubbles framed on the electrode associated with the positive terminal of the battery and hydrogen bubbles shaped on the other electrode.

Electroplating:

The most common way of saving a layer of any ideal metal on another material, through electricity, is called electroplating. It is the most normal use of chemical effects of electric flow.

  • Electroplating is widely used in industry for coating metals with a thin layer of a different metal
  • Chromium plating is done on many articles, for example, vehicle parts, shower taps, and so forth
  • Jewellery producers electroplate silver and gold on more affordable metals
  • Metal jars are made by electroplating tin on iron
  • A covering of zinc is saved on iron to shield it from corrosion and rusting
  • In the electroplating manufacturing plants, the removal of the pre-owned directing arrangement is a main issue. It is a contaminating waste and there are explicit removal rules to ensure the climate

Key Terms and Facts

  • Materials which allow electric current to pass through them are good conductors of electricity such as copper and aluminium
  • Materials which do not allow electric current to pass through them easily are poor conductors of electricity such as rubber, plastic, and wood
  •  A few liquids are great channels of power, and some are poor conductors
  •  Most liquids that lead electricity are arrangements of acids, bases, and salts
  • Refined water is liberated from salts and is a poor conductor
  • At the point when salt is broken down in refined water, the subsequent salt arrangement is a conductor of electricity
  • A terminal is a strong electric conduit that conveys electric flow into non-metallic solids, or  liquids, or gases

Important Facts

  • Good conductors of electricity are materials that allow electric current to pass through them. Metals such as copper and aluminium are examples
  • Poor conductors of electricity are materials that do not easily allow electric current to pass through them. Rubber, plastic, and wood are a few examples
  • As a result of the heating effect of current, the filament of the tester’s bulb heats up to a high temperature and begins to glow
  • If the current flowing through a circuit is insufficient, the filament does not heat up sufficiently and does not glow
  • LED (Light Emitting Diodes) can be used in place of the tester’s electric bulb; LED glows even when only a weak electric current passes through it
  • Because an electric current generates magnetic current, a tester can be made by using a compass needle
  • Even when the current is low, the magnetic needle can be seen deflecting. • Distilled water is a poor electrical conductor
  • Water collected from taps, hand pumps, wells, and ponds is not pure and contains dissolved salts, making it an excellent conductor of electricity
  • The majority of liquids that conduct electricity are solutions of acids, bases, and salts
  • Electric current chemical effect: The passage of an electric current through a conducting solution causes a chemical reaction
  • This may result in the formation of gas bubbles on the electrodes, metal deposits on the electrodes, changes in the colour of solutions, and so on
  • Electroplating: Electroplating is the process of depositing a layer of any desired metal on another material using electricity.It is one of the most common applications of the chemical effects of electric current
  • As a result, gas bubbles on the electrodes may form
  • Electroplating Applications: Electroplating is widely used in industry to coat metal objects with a thin layer of a different metal
  • This can be done to — make objects appear shiny, — prevent corrosion, — make objects scratch resistant. — protect less reactive metals by coating them with more reactive metals; — make ornaments by electroplating less expensive metals with silver and gold

For example, chromium has a gleaming appearance, does not corrode, and is scratch resistant. However, chromium is expensive, and it is not cost effective to make the entire object out of chromium. As a result, objects such as taps, car parts, wheel rims, and so on are made of a cheaper metal and electroplated with chromium.

  • Jewellery made of a cheaper metal is electroplated with silver or gold to appear to be made of silver or gold. Tin has a lower reactivity than iron. To prevent spoilage from contact with iron, iron cans used for food are electroplated with tin
  •  Iron used in bridges and automobiles is electroplated with a zinc coating to protect it from corrosion and rust formation.• The disposal of electroplating factories’ used conducting solution is a major issue. It is a polluting waste, and specific disposal guidelines are in place to protect the environment

Applications of Electroplating: 

We’ve all seen fake jewellery that shines when it’s new but quickly loses its lustre. The same is true for bicycle handlebars, nuts, and bolts, among other things. This is because these metals are coated with another metal to give them a lustrous appearance while remaining economically viable.

Highlights: 

  • Artificial jewellery is frequently plated with a thin layer of a precious metal, such as gold or silver, to make it more lustrous and appealing while remaining less expensive
  • Electroplating is used in many industrial applications to create a protective barrier on a metal substrate. In this case, the protective barrier prevents tarnishing and provides a glossy appearance. For example, chromium plating is done on car spare parts, taps, wheel rims, and so on. Chromium is extremely expensive, and the entire part cannot be made of it. As a result, it is coated with chromium to give it a gleaming appearance
  • Tinning (electroplating tin) is a low-cost electroplating solution. Tin is a less expensive metal that is used for electroplating electronic components, hardware, fasteners, screws, nuts, bolts, and food cans. Food that is stored in iron cans tends to spoil over time. But, when iron is electroplated with tin, it prevents the food from getting spoiled. Tinning offers resistance against corrosion
  • Zinc electroplating provides excellent adhesion and corrosion resistance. As a result, it is used to electroplate automobile body parts, transmission components, defence carriers, and tanks

Conclusion

An electric current passing through a conducting solution causes chemical reactions. As a result, gas bubbles may form on the electrodes. Metal deposits on electrodes are possible. Colour changes in solutions are possible. The reaction would be affected by the solution and electrodes used.