Chemical Effects of Electric Current

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We use electricity to run different appliances or other things such as doorbells, heaters, bulbs, fans, and many more. The chemical effect of electricity can be explained on these devices as well, and there are many ways to define chemical effects of electric current in brief. These devices make use of various effects of electric current like the heating effect and magnetic effect. Its chemical effect is another often-used effect of electric current. When electricity is passed through some specific liquids, chemical changes take place. Some of these changes are quite important to us.

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How is it Possible to Pass Electricity Through a Liquid? Let Us Look at It

Let us put two electrodes in the liquid and apply a fixed voltage across them. In a circuit, an electrode is a conductor being in contact with a nonmetallic thing, like liquid or gas. The electrode which is connected to the battery's positive terminal is known as the anode, whereas the electrode connected to the negative terminal is known as the cathode.

During rainy seasons we are often told to stay away from the electric poles. If we ever wondered why it is so, as the water flows continuously, the insulator turns into a conductor. Resultantly, electricity can flow through our bodies.

Thermal and Chemical Effects of Electric Current

The thermal and chemical effects of electric current are described briefly below. Let us have a look at these two factors.

Chemical Effects of Electric Current

This is a chemical effect of electricity that can be explained in terms of chemical properties. We all know that when an electric current passes through a solution, it ionizes and breaks down into ions. This is because of the chemical reactions that happen when an electric current passes through a solution. The electric current and its chemical effects are given below to identify easily. Based on the electrodes used and the nature of the solution, the following effects can be noticed in the solution:

  • A Change in the colour of the solution

  • Metallic deposits on the electrodes

  • Production of bubbles or a release of gas in the solution

Thermal Effects of Electric Current

Some of the thermal effects of electric current are given below.

Heating Effect - Let us look at the electricity and its heating and chemical effects thoroughly. The electric current makes heating of the electrical equipment. For example, the filament in a bulb gets heated up because of the electric current and glows, therefore.

Mechanical Effect - electric current can lead to the generation of mechanical energy in appliances. For example, motors and fans work due to this effect.

Magnetic Effect - electric current can lift upward to the magnetic field of a substance, which is a well-known chemical effect of electricity.

Chemical Effect - electric current can lead to the production of chemical reactions or chemical energy.

Application of Chemical Effect of Electric Current

  1. Extracting Metals from Their Ores

Pure metals are extracted from the metal ores by the electrolysis process. Electricity is passed via the metal ores, and the ores get broken down into an ionic lattice, and thereby the metal obtains separately. For example, metals like magnesium, aluminium, potassium, calcium, and sodium are obtained from their ores in this way, which is a widely accepted application of chemical effect of electric current.

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  1. Purification of Metals

The electrolysis method is used to purify metal by separating it from the impurities. The impure metal can be used as an anode that dissolves in the electrolyte solution first and later deposits on the cathode in the pure form. The metal impurities remain in the electrolyte solution only. Metals like aluminium, copper, and zinc are purified in this way.

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  1. Production of Compounds

This electrolysis method is used for the production of some compounds, such as sodium hydrochloride. It is the easiest application of chemical effect of electric current.

  1. Decomposition of Compounds

The electrolysis method is used to decompose a compound into its constituents. For example, water is decomposed with the process of electrolysis to obtain oxygen and hydrogen.

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  1. Electroplating

Electroplating is a process where a layer of one metal is coated with another metal using the electrolysis method.

Electroplating Process for a Silver Spoon with Gold

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  • To coat the silver spoon with gold, we select the metal's acidified solution to be coated (gold chloride with the hydrochloric acid) as an electrolyte and the article (silver spoon) to be electroplated is selected as a cathode.

  • Then, take a thick plate of the metal (gold plate) to be deposited as an anode.

  • Now, the silver spoon should be cleaned with a dilute acid solution to remove the oxide layer from its surface and then washed in running water until it is free from the acid.

  • Thus, the cleaned silver spoon is suspended in the acidified gold chloride solution (electrolyte) kept in a beaker.

  • Also, the thick plate of gold (selected as an anode) is suspended in the gold chloride solution.

  • The circuit is then completed using a battery and a key.

  •  Let the current pass through it for around 15 minutes and then remove the electrodes from the solution.

  • Therefore, the silver spoon will look like a gold spoon.

Uses of Electroplating

Some famous uses of electroplating are given as,

  • This is the most extensive use of gold plating used on watch cases and jewellery.

  • Zinc coating prevents the corrosion of steel articles.

  • Chromium and nickel-coated articles are used in household appliances and automobiles.

FAQ (Frequently Asked Questions)

1. Explain Chemical Effect of Electric Current on Water?

  • Various substances, when mixed in water and electricity, are passed through them, can break apart and form the positive and negative particles or water ions.

  • These ions resultantly pass the electric current through them.

  • The more ions in a liquid, the better the conductor is the electricity.

  • Thus, distilled water is a poor conductor of electricity whereas saltwater is a good conductor of electricity.

  • Many compounds, however, do not form any ions on mixing them with water, and thus they are poor conductors of electricity like oil, sugar water, and alcohol.

The diagrammatic representation of setting up to detect if a liquid can conduct electricity is given below.

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2. Why Are LED Bulbs Highly Suitable for Testing the Electrical Conductivity of Liquids?

The electric current often causes the heating effect because the bulb's filament gets heated up and glows thereby.

Some of the liquids are capable of conducting electricity, but they are the weak conductors of electricity. Consequently, the current passes through them is not that strong enough to heat the filament. Due to this, the filament would not light up in such a case of liquids.

The LED bulbs, however, can be able to detect the flow of even a small amount of electric current also. Therefore, the LED bulbs are highly suitable for testing the electrical conductivity of liquids.