Ch 4 compares metals and non-metals based on their physical and chemical properties. Students learn about reactions with acids, oxygen, and water, and the concept of displacement reactions.
Metals: shiny (lustre), hard, malleable (can be hammered into sheets), ductile (drawn into wires), good conductors of heat and electricity, high melting points. Exceptions: mercury is liquid, sodium is soft. Non-metals: dull, brittle, poor conductors. Exception: diamond is hard, graphite conducts electricity.
Metal + oxygen → metal oxide (basic nature). Non-metal + oxygen → non-metal oxide (acidic nature). Metal + acid → salt + hydrogen gas. Displacement reaction: a more reactive metal displaces a less reactive metal from its salt solution (e.g., iron displaces copper from CuSO₄).
Download: https://ncert.nic.in/textbook/pdf/hesc104.pdf | Complete book: https://ncert.nic.in/textbook/pdf/hesc1ps.zip
Copper is an excellent conductor of electricity (second only to silver) and is ductile (can be drawn into thin wires). It is also resistant to corrosion and relatively affordable compared to silver, making it ideal for electrical wiring.
Book a Trial + Diagnostic session. Get a personalized Learning Path with clear milestones, tutor match, and a plan recommendation — all within 24 hours.
Book Trial + Diagnostic →