Class 10 Science Chapter 3: Metals and Non-metals – NCERT Solutions Notes Metals and Non-metals is an important chapter in Class 10 Science that explains the physical and chemical properties of metals and non-metals, their reactions, and uses. It is highly conceptual and frequently asked in exams. These notes are structured for clear understanding and quick revision. Key Concepts Metals Metals are elements that are generally hard, shiny, malleable, ductile, and good conductors of heat and electricity. Examples: Iron, copper, aluminium, zinc Non-metals Non-metals are elements that are generally dull, brittle, and poor conductors of heat and electricity. Examples: Oxygen, nitrogen, sulphur, carbon Physical Properties Metals Lustrous (shiny) Malleable (can be beaten into sheets) Ductile (can be drawn into wires) Good conductors of heat and electricity Sonorous (produce sound when struck) Non-metals Dull appearance Brittle (break easily) Poor conductors Not sonorous Chemical Properties of Metals Reaction with Oxygen Metal + Oxygen → Metal oxide Example: 2Mg + O₂ → 2MgO Metal oxides are usually basic in nature. Reaction with Water Some metals react with water to form hydroxides and hydrogen gas. Example: 2Na + 2H₂O → 2NaOH + H₂ Reaction with Acids Metal + Acid → Salt + Hydrogen gas Example: Zn + 2HCl → ZnCl₂ + H₂ Reactivity Series A list of metals arranged in decreasing order of reactivity. Most reactive → Least reactive K > Na > Ca > Mg > Al > Zn > Fe > Pb > Cu > Ag > Au Displacement Reaction A more reactive metal displaces a less reactive metal from its salt solution. Example: Zn + CuSO₄ → ZnSO₄ + Cu Ionic Compounds Metals lose electrons to form positive ions, non-metals gain electrons to form negative ions. Example: Na → Na⁺ + e⁻ Cl + e⁻ → Cl⁻ Na⁺ + Cl⁻ → NaCl Occurrence of Metals Minerals Naturally occurring substances containing metals. Ores Minerals from which metals can be extracted profitably. Extraction of Metals Steps: Concentration of ore Conversion to oxide Reduction to metal Refining Corrosion Slow damage of metals due to reaction with air, moisture, or chemicals. Example: Rusting of iron Prevention of Corrosion Painting Galvanization Oiling and greasing Alloy formation Important Alloys Brass = Copper + Zinc Bronze = Copper + Tin Steel = Iron + Carbon NCERT Important Questions (Concept Based) Why are metals good conductors of electricity? Because they have free electrons. Why is sodium stored in kerosene? Because it reacts violently with air and water. What is corrosion? Gradual destruction of metals due to environmental reactions. Important Reactions to Remember 2Mg + O₂ → 2MgO Zn + CuSO₄ → ZnSO₄ + Cu 2Na + 2H₂O → 2NaOH + H₂ Why this chapter is important This chapter builds the foundation of chemical reactivity and industrial applications. It is frequently asked in exams in: Reaction-based questions Reactivity series Reasoning questions NCERT exercises Final Revision Tip Focus on: Reactivity series Metal vs non-metal properties Extraction steps Important chemical reactions