Chemical Effects of Electric Current
What is electric current?
An electric current is the flow of electric charge. In electric circuits this charge is often carried by moving electrons, in a wire. It is either Direct Current (DC) or Alternating Current (AC).
Electric currents cause heating in certain metals like tungsten, which creates light in incandescent light bulbs. They also create magnetic fields, which are used in motors, inductors and generators.
The SI unit for measuring an electric current is the Ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second. Electric current is measured using a device called an ammeter.
What happens when electric current is passed through a substance?
When electric current is passed through solids, it can either conduct the current, in which case, the material is a good conductor of electricity. At times, either magnetic effect, heat or light is generated.
Example : Iron, Copper, Gold, Platinum, Silver, Tungsten
Incase a solid doesn’t allow the current to pass through, it means it is a bad conductor or insulator of electricity.
Example : Wax, Wood, Plastic, Glass
When electric current passes through gases, light maybe generated.
When electric current is passed through a liquid (electrolyte), it causes a chemical reaction that separates ions. This process is known as Electrolysis.
What is electrolysis?
Electrolysis is the process when a liquid/solution of minerals, salt, etc, undergoes a chemical reaction when electrical current (Direct Current) is passed through it. A chemical reaction maybe defined as an exchange of ions. In this process ions are either absorbed or released.
Who coined the term electrolysis?
The term Electrolysis was coined by Michael Faraday, in 1832. He even discovered the two laws of Electrolysis, known as Faraday’s Law of Electrolysis.
Faraday’s 1st Law of electrolysis
According to this Law, the physical quantity of elements separated by passing electrical current through a molten or dissolved salt is proportional to the quantity of electric charge passed through the circuit.
Faraday’s 2nd Law of electrolysis
According to this Law, when the same amount of current is passed through different electrolytes/elements connected in series, the mass of substance liberated/deposited at the electrodes is directly proportional to their equivalent weight.
What are the uses of electrolysis?
Electrolysis is used in many industrial processes: separation of metals and minerals from ores and mineral salts coating of one metal with another, ie., electroplating