Bright Tutorials Bright Tutorials
ICSE Class 7 Chemistry Question 16 of 16

Metals and Non-metals — Question 16

Back to all questions
16
Question

Question 16

State a specific reason for using –

(a) steel in automobiles

(b) gold in jewellery

(c) copper in electrical cables

(d) zinc in galvanizing

(e) lead in bullets

(f) magnesium in fireworks.

Answer

(a) Steel in automobiles — It is malleable with high tensile strength.

(b) Gold in jewellery — It is expensive, lustrous, malleable and ductile.

(c) Copper in electrical cables — It is a good conductor of electricity.

(d) Zinc in galvanizing — It prevents rusting.

(e) Lead in bullets — It has high specific gravity.

(f) Magnesium in fireworks — It burns with a dazzling light.

ICSE Class VII Chemistry Chapter 5 14 Marks

Metals and Non-Metals — Quick Study Guide

Elements are broadly classified as metals, non-metals, or metalloids based on their physical and chemical properties.

Key Properties

  • Metals: Lustrous, malleable, ductile, sonorous, good conductors, high density
  • Non-metals: Dull, brittle, poor conductors, non-sonorous, low density
  • Metalloids: Properties of both (e.g., Silicon, Germanium)

Chemical Reactions

  • Metal + O2 → Basic oxide (turns red litmus blue)
  • Non-metal + O2 → Acidic oxide (turns blue litmus red)
  • Metal + Acid → Salt + H2

Exam Tips

  • Know all exceptions: Mercury (liquid), Graphite (conducts), Diamond (lustrous), Na/K (soft)
  • Learn the comparison table (8 properties) thoroughly
  • Practice writing equations for metal reactions
  • Know uses of at least 5 metals and 5 non-metals

Bright Tutorials | ICSE Class VII Chemistry | Chapter 5: Metals and Non-Metals | Contact: 9403781999