Grade 7
  1. Introduction to Chemistry  1.1. What is Chemistry?  1.2. Importance of chemistry in daily life  1.3. Branches of chemistry  1.4. Scientific Method in Chemistry  1.5. Laboratory Safety Rules and Precautions  1.6. Common Laboratory Equipment and Their Uses  1.7. Units of measurement in chemistry
  2. Matter and its properties  2.1. Definition of Matter  2.2. Classification of matter  2.3. Properties of matter  2.3.1. Physical properties  2.3.2. Chemical properties  2.4. States of matter  2.4.1. Solid state  2.4.2. Fluid state  2.4.3. Gaseous state  2.4.4. Plasma and Bose–Einstein condensates  2.5. Changes in the states of matter  2.5.1. Melting and freezing  2.5.2. Evaporation and Condensation  2.5.3. Sublimation and deposition  2.6. Density and its applications  2.7. Diffusion and its importance
  3. Elements, Compounds, and Mixtures  3.1. Definition of the element  3.2. Classification of elements  3.3. Metals, Nonmetals and Metalloids  3.4. Noble gases and their properties  3.5. Introduction to the Periodic Table  3.6. Definition of Compound  3.7. Properties of Compounds  3.8. Introduction to Chemical Formulas  3.9. Definition of Mixture  3.10. Types of mixtures  3.10.1. Homogeneous mixture  3.10.2. Heterogeneous mixtures  3.11. Difference Between Compounds and Mixtures  3.12. Solutions, Colloids and Suspensions
  4. Separation of mixtures  4.1. Need for separation of mixtures  4.2. Separation methods  4.2.1. Filtration  4.2.2. Sedimentation and decantation  4.2.3. Evaporation  4.2.4. Crystallization  4.2.5. Distillation  4.2.6. Chromatography  4.2.7. Magnetic Separation  4.2.8. Centrifugation
  5. Atomic Structure  5.1. Introduction to Atoms  5.2. Structure of the atom  5.2.1. Nucleus and electron cloud  5.3. Subatomic particles  5.3.1. Proton  5.3.2. Neutron  5.3.3. Electrons  5.4. Atomic number and mass number  5.5. Isotopes and their uses  5.6. Ions and ion formation
  6. Periodic table  6.1. Introduction to the Periodic Table  6.2. Groups and periods  6.3. Trends in the Periodic Table  6.3.1. Atomic Size  6.3.2. Metallic and non-metallic character  6.3.3. Electronegativity  6.3.4. Reactivity of the elements  6.4. Alkali metals and their properties
  7. Chemical bond  7.1. Why do atoms form bonds?  7.2. Types of chemical bonds  7.2.1. Ionic bond  7.2.2. Covalent bond  7.2.3. Metal Bond  7.3. Properties of Ionic and Covalent Compounds  7.4. Intermolecular forces
  8. Chemical reactions  8.1. Introduction to Chemical Reactions  8.2. Signs of a chemical reaction  8.3. Types of Chemical Reactions  8.3.1. Combination Reactions  8.3.2. Decomposition reactions  8.3.3. Displacement reactions  8.3.4. Double displacement reactions  8.3.5. Combustion reactions  8.4. Law of conservation of mass  8.5. Balancing simple chemical equations
  9. Acids, Bases and Salts  9.1. Definition of Acid and Base  9.2. Properties of Acids  9.3. Properties of bases  9.4. pH Scale and Indicators  9.5. Neutralization reactions  9.6. Common Acids and Bases in Everyday Life  9.7. Preparation and use of salts  9.8. Strong and weak acids and bases
  10. Solutions and Solubility  10.1. Definition of Solution  10.2. Components of the solution  10.2.1. Solvent  10.2.2. solute  10.3. Factors Affecting Solubility  10.4. Concentration of solutions  10.5. Saturated and unsaturated solutions  10.6. Colloids and suspensions  10.7. Solubility curve and its interpretation
  11. Air and atmosphere  11.1. Composition of air  11.2. Properties of gases in the air  11.3. Importance of Oxygen and Carbon Dioxide  11.4. Air pollution and its effects  11.5. Greenhouse effect and global warming  11.6. Ways to reduce air pollution  11.7. Ozone layer and its importance
  12. Water and its importance  12.1. Properties of Water  12.2. Water as the universal solvent  12.3. Importance of water for life  12.4. Water pollution and its effects  12.5. Water Purification  12.5.1. Filtration  12.5.2. boil  12.5.3. Chlorination in water purification  12.5.4. reverse osmosis  12.6. Hard and soft water  12.7. Water cycle and its importance
  13. Fuel and energy  13.1. Types of fuel  13.1.1. Fossil fuels  13.1.2. Renewable energy sources  13.2. Combustion and energy release  13.3. Global warming and its effects  13.4. Alternative sources of energy  13.5. Ways to conserve energy
  14. Metals and Nonmetals  14.1. Physical and chemical properties of metals  14.2. Physical and Chemical Properties of Non-Metals  14.3. Difference Between Metals and Nonmetals  14.4. Uses of metals and nonmetals  14.5. Corrosion of metals and its prevention  14.6. Alloys and their importance
  15. Plastics and polymers  15.1. Natural and synthetic polymers  15.2. Properties of plastics  15.3. Biodegradable and Non-Biodegradable Plastics  15.4. Environmental impact of plastic  15.5. Recycling and waste management in plastics and polymers  15.6. Daily Uses of Polymers
  16. Introduction to Organic Chemistry  16.1. Basic definitions of organic chemistry  16.2. Carbon Compounds in Daily Life  16.3. Hydrocarbons  16.4. Simple functional groups (alcohols and carboxylic acids)  16.5. Importance of organic compounds in industry

Grade 7 → Separation of mixtures → Separation methods ↓


Magnetic Separation


In the world of chemistry, understanding how to separate the different components of a mixture is a vital skill. One of the fundamental methods used is "magnetic separation." Although the concept may seem complex, it simply involves separating materials based on magnetic properties. In this explanation, we will explore how magnetic separation works, why it is important, and provide examples for a broader understanding.

What is magnetic separation?

Magnetic separation is a process in which magnetically sensitive materials are extracted from a mixture using magnetic force. Think of it in simple terms as a way of sorting things into those that can stick to a magnet and those that cannot. This process works because magnets attract certain metals. If a metal is magnetic, it will be drawn towards the magnet, while non-magnetic materials will not be attracted.

How does magnetic separation work?

The principle behind magnetic separation is very simple. Here is a simplified explanation:

  • A mixture is placed in a magnetic field.
  • Magnetically sensitive substances stick to magnets.
  • Non-magnetic materials remain unaffected and can be separated.
Magnet

In the simple illustration above, imagine the red circle as a piece of iron, which is magnetic, and the blue circle as a piece of plastic, which is non-magnetic. When exposed to a magnetic field (shown in green), the iron piece is pulled toward the magnet, while the plastic piece stays in place.

Why is magnetic separation useful?

Magnetic separation is widely used due to its efficiency and simplicity. Here are some scenarios in which magnetic separation is beneficial:

  1. Beneficiation of magnetite: Beneficiation is the process of extracting valuable minerals from ores. Magnetite ores are iron-rich rocks that are often beneficiated using magnetic separation to separate the iron.
  2. Recycling: In recycling facilities, magnets are used to remove ferrous metals from a mixed waste stream, improving the quality of recyclable materials.
  3. Mining: Mining industries use magnetic separation to extract iron ore and minerals from other rocks and materials, making the extraction process more efficient.
  4. Food industry: To ensure food safety, magnetic separators can remove small metal particles from grains and cereals.

Examples of magnetic separation

Example 1: Iron and sand

Imagine you have a mixture of iron filings and sand. You want to separate the iron filings from the sand. Magnetic separation will help as follows:

  • Spread the mixture on a tray.
  • Bring a magnet close to the surface of the mixture.
  • The iron filings, which are magnetic, will stick to the magnet.
  • The sand will be left behind.
Iron Sand

In this example, by using just a magnet, you have separated the iron from the sand without any effort.

Example 2: Recycling of scrap metal

At a recycling plant, you may find a mixture of aluminum and steel cans. Aluminum is non-magnetic while steel is magnetic. Here's how plants use magnetic separation:

  • The scrap metal mixture is passed over large magnetic belts.
  • The steel cartons are pulled by a magnetic belt.
  • Aluminium cans fall down unaffected by the magnetic field.

The science behind magnetic separation

To understand this science it is necessary to have a little knowledge about magnetic properties:

Magnetic materials

Substances can be classified as ferromagnetic, paramagnetic, or diamagnetic depending on their response to magnetic fields:

  • Ferromagnetic: Materials such as iron, cobalt, and nickel that are strongly attracted to magnets.
  • Paramagnetic: Materials such as aluminum and platinum that are weakly attracted to magnets.
  • Diamagnetic: Materials such as copper and bismuth that are weakly repelled by magnets.

The target for magnetic separation is ferromagnetic materials, because they respond most effectively to magnetic fields.

Magnetic force

The formula describing the magnetic force (F) acting on a particle is:

F = m × H

Where m is the magnetic moment and H is the magnetic field strength.

Benefits and limitations

Like any other method, magnetic separation has its advantages and disadvantages:

Benefit

  • Simplicity: The process is straightforward and does not require complicated equipment.
  • Efficiency: Magnetic separation is efficient and is completed quickly.
  • Cost effective: It does not use expensive chemicals or processes.
  • Versatility: Can be adapted to different scales, from small laboratory procedures to large industrial operations.

Limitations

  • Material limitation: Works only for magnetic materials.
  • Not suitable for liquids: Usually used for solid-solid mixing.
  • Separation of particles: Small magnetic particles may require special design considerations.

Conclusion

Magnetic separation serves as an important method for separating mixtures in a variety of fields, from mining to recycling. Its ability to efficiently and effectively separate magnetic materials makes it invaluable in both industrial and scientific processes. Whether sorting ores in mining or extracting metals from recyclable materials, magnetic separation remains an essential tool in the chemist's toolbox.


Grade 7 → 4.2.7


U
username
0%
completed in Grade 7

← Prev (4.2.6)
Chromatography
Next (4.2.8) →
Centrifugation

Comments 



Magnetic Separation

https://www.chemistryelite.com/g7/4.2.7?ceal=en