Class 10 Science Chapter 17 Metals is one of the most informative and exam-important chapters in your science syllabus. In this chapter, you will explore the properties of metals and non-metals, the difference between minerals and ores, ores of important metals like iron, aluminium, copper, silver and gold, and the complete metallurgical process including mining, concentration, reduction, and refining. From understanding why gold is the most ductile metal to learning how electro-refining purifies impure metals, this complete guide to Class 10 Science Chapter 17 Metals will help you master every concept and process with clarity and confidence.
Introduction
The Earth’s crust is made up of various elements, including metals and non-metals, each with distinct properties and uses in our daily life.
What are Metals?
Metals are elements that:
- Are generally solid at room temperature (except mercury)
- Shiny (lustrous)
- Good conductors of heat and electricity
- Malleable and ductile
- Form positive ions (cations)
Main Properties of Metals:
| Property | Description |
| Malleability | Can be hammered into thin sheets |
| Ductility | Can be drawn into wires |
| Conductivity | Good conductors of heat and electricity |
| Lustrous | Have shiny appearance |
| Sonorous | Produce sound when struck |
| High melting/boiling points | Generally high |
What are Non-Metals?
Non-metals are elements that:
- Are usually gases or brittle solids
- Are poor conductors of heat and electricity
- Tend to gain electrons to form negative ions (anions)
Main Properties of Non-Metals:
| Property | Description |
| Brittle | Break easily; not malleable or ductile |
| Poor conductors | Except graphite, they don’t conduct electricity |
| Non-lustrous | Usually dull in appearance |
| Low density | Often lighter than metals |
| Low melting points | Usually lower than metals |
Minerals and Ores
What are Minerals?
- Naturally occurring inorganic substances found in Earth’s crust.
- May or may not contain metals in extractable form.
What are Ores?
- Minerals that contain metal in a profitable or economical form.
- Example: Bauxite is an ore of aluminium.
Ores of Some Important Metals
Iron Ores:
| Ore Name | Molecular Formula | Description |
| Hematite | Fe₂O₃ | Main ore of iron, reddish in color |
| Magnetite | Fe₃O₄ | Magnetic ore, black |
| Limonite | Fe₂O₃·3H₂O | Brown iron ore, hydrated oxide |
| Siderite | FeCO₃ | Carbonate ore of iron |
Aluminium Ores:
| Ore Name | Molecular Formula | Description |
| Bauxite | Al₂O₃·2H₂O | Main ore of aluminium |
| Cryolite | Na₃AlF₆ | Used in aluminium extraction (not main ore) |
| Corundum | Al₂O₃ | Used as abrasive, gemstone form exists |
Copper Ores:
| Ore Name | Molecular Formula | Description |
| Chalcopyrite | CuFeS₂ | Major copper ore |
| Cuprite | Cu₂O | Red oxide of copper |
| Malachite | CuCO₃·Cu(OH)₂ | Green carbonate ore |
Silver Ores:
| Ore Name | Molecular Formula | Description |
| Argentite | Ag₂S | Primary ore of silver |
| Horn Silver | AgCl | Occurs in dry regions |
Gold Ores:
| Ore Name | Molecular Formula | Description |
| Native Gold | Au | Found as pure metal in rocks |
| Sylvanite | (Ag,Au)Te₂ | Gold telluride |
| Calaverite | AuTe₂ | Gold telluride ore |
Metallurgy – Class 10 Science Chapter 17 Metals
Metallurgy is the science of extracting metals from their ores and refining them for use.
Mining
Mining is the process of extracting ores from Earth’s crust.
General Steps of Metallurgical Process
a. Crushing and Grinding
- Ores are crushed into fine particles to liberate the metal content.
b. Concentration of Ore (Enrichment)
To remove unwanted materials (gangue) using methods like:
i. Gravity Separation
- Based on difference in density (used for heavy oxide ores).
ii. Froth Flotation
- Used for sulphide ores.
- Ore is mixed with water and chemicals; froth traps the ore particles.
iii. Magnetic Separation
- Used when one of the components is magnetic (e.g. magnetite).
iv. Leaching
- Ore is dissolved in a chemical solution; the metal is later recovered from the solution.
c. Oxidation (Conversion to Oxide)
i. Roasting
- Heating ore in air (used for sulphide ores).
- Example: ZnS → ZnO + SO₂
ii. Calcination
- Heating in absence of air (used for carbonate ores).
- Example: CaCO₃ → CaO + CO₂
d. Reduction
Reduction involves converting metal oxides to pure metal.
Smelting:
- Melting the ore and reducing it with a reducing agent like carbon.
e. Refining of Metals
Purification of extracted metal. Common methods include:
i. Distillation
- Used for low boiling point metals like zinc and mercury.
ii. Electro-refining
- Impure metal acts as anode, pure metal gets deposited on cathode.
Interesting Facts:
- Gold is the most ductile metal—1 gram can be drawn into a 2 km wire.
- Aluminium is the most abundant metal in Earth’s crust.
- Silver is the best conductor of electricity among all metals.
- Bauxite is so important that aluminium is often called the “metal of the future.”
- Froth flotation was first developed in the early 20th century and revolutionized metal mining.
Quick Revision Table:
| Topic | Key Points |
| Metal properties | Malleable, ductile, lustrous, conductors |
| Non-metal properties | Brittle, dull, poor conductors |
| Ore vs Mineral | Ore is profitable, mineral is natural substance |
| Main iron ores | Hematite (Fe₂O₃), Magnetite (Fe₃O₄) |
| Concentration methods | Gravity, flotation, magnetic, leaching |
| Roasting vs Calcination | Roasting = air, Calcination = no air |
| Refining methods | Distillation, electro-refining |
This completes the full revision of Class 10 Science Chapter 17 Metals.
