Chemical Effects of Electric Current: Bridging Electricity and Chemistry
Electricity is not just about illuminating bulbs or running gadgets. At a microscopic level, it can cause fascinating chemical changes. Chapter 14 unravels the intricate dance between electricity and chemicals, shedding light on phenomena we see in daily life.
1. Introduction
When an electric current passes through a substance, it can induce a chemical change, especially if the substance is a liquid. This interaction of electricity and chemicals is fundamental to several industrial processes and even some biological ones.
2. Conductors and Insulators
- Conductors: Materials that allow electric current to pass through them. Most metals, such as copper and aluminum, are good conductors.
- Electrolytes: These are liquid conductors, generally solutions, which can conduct electricity. Examples include saltwater and lemon juice.
- Insulators: Materials that do not allow electric current to flow through them, like rubber and glass.
3. Electrolysis
Electrolysis is the process where an electric current is passed through an electrolyte, causing a chemical reaction. Here’s how it works:
- An electric circuit is set up with two electrodes (typically made of graphite or metal) immersed in an electrolyte.
- When current flows, positive ions move towards the negative electrode and receive electrons, undergoing reduction. Simultaneously, negative ions move to the positive electrode, lose electrons, and undergo oxidation.
4. Applications of Electrolysis
Electrolysis has a broad range of applications, including:
- Electroplating: Using electrolysis to coat a metal object with another metal.
- Extraction of metals: Electrolysis helps in extracting metals from their ores, especially metals like aluminum.
- Manufacture of chemicals: Products like chlorine and sodium hydroxide are produced via electrolysis.
5. Electroplating
This is one of the most common applications of the chemical effects of electric current. The primary purpose is to coat objects with a thin layer of a different metal. Reasons for electroplating:
- Beauty and shine: Objects like jewelry are electroplated with gold or silver for a shiny finish.
- Prevention of corrosion: Metals like iron, which are prone to rusting, are coated with metals like nickel or chromium.
- Better conductivity: Some metals conduct electricity better than others. Electroplating can enhance conductivity.
6. LEDs: Indicators of Conduction
Light Emitting Diodes (LEDs) only allow current to flow in one direction. They are used as indicators to check if a liquid allows electricity to pass through it or not. When the liquid conducts electricity, the LED glows.
7. Effects on Humans
While the chemical effects of electric current are immensely beneficial, direct exposure to electricity can be harmful. The human body is a good conductor of electricity, and accidental exposure can lead to injuries or even be fatal. Always handle electrical devices with caution.
8. Conclusion
The intertwined realms of electricity and chemistry open a world of technological and industrial wonders. From the golden shimmer of your jewelry to the anti-rust coating on your bike, the chemical effects of electric current play an integral role in shaping our surroundings.
Note: This article provides an SEO-optimized overview of Chapter 14 ‘Chemical Effects of Electric Current’ from the Grade 8 Science NCERT textbook. For a thorough understanding and in-depth insights, students are advised to refer to the original NCERT material.
