Metals and Non-metals Notes

Metals and Non-metals

  • Metals are common elements, as they all contain some metal.

Images

  • Common elements in images include oxygen.

Classification of Elements

  • Elements are classified into metals, non-metals, and metalloids.

  • Examples of metals: Gold, silver, copper, tin, lead, iron.

  • Examples of non-metals: Carbon, oxygen, nitrogen, phosphorus, sulphur, iodine.

  • Examples of metalloids: Boron, silicon, germanium, arsenic, antimony, tellurium.

Properties of Metals and Non-metals

  • Physical properties:

    • Lustre

    • Malleability

    • Ductility

    • Electrical conductivity

    • Tensile strength

    • Hardness

    • Sonority

    • Brittleness

  • Chemical properties:

    • Electropositive and electronegative nature

    • Ions

    • Electronic configuration

    • Nature of oxides

    • Reaction with hydrogen

    • Reaction with chlorine

    • Reducing/oxidizing nature

Physical Properties

  • Physical state:

    • Metals: Generally solid due to high melting point, except mercury and gallium (liquid at room temperature).

    • Non-metals: Exist in all three states (gas, liquid, solid). Examples: Gas - hydrogen, chlorine, oxygen; Liquid - bromine; Solid - iodine, sulphur, carbon.

  • Malleability:

    • Metals: Generally malleable (e.g., gold, silver).

    • Non-metals: Not malleable (e.g., crystals of iodine).

  • Ductility:

    • Metals: Ductile (e.g., silver, gold, copper).

    • Non-metals: Not ductile (e.g., carbon).

  • Thermal conductivity:

    • Metals: Good conductors of heat (silver is the best, lead is the poorest).

    • Non-metals: Bad conductors (e.g., phosphorus).

  • Electrical conductivity:

    • Metals: Good conductors of electricity (e.g., copper).

    • Non-metals: Bad conductors, except graphite and iodine.

Lustre, Hardness, and Tensile Strength

  • Lustre:

    • Metals: Possess lustre (e.g., gold).

    • Non-metals: Lack lustre, except graphite and iodine.

  • Hardness:

    • Metals: Hard, except sodium and potassium (soft metals).

    • Non-metals: Generally soft, except diamond.

  • Tensile strength:

    • Metals: High tensile strength.

    • Non-metals: Low tensile strength.

  • Sonority:

    • Metals: Sonorous (e.g., tin).

    • Non-metals: Non-sonorous (e.g., sulphur).

  • Melting and boiling point:

    • Metals: High melting and boiling points (tungsten has the highest melting point).

    • Non-metals: Low melting and boiling points.

  • Definition: Alloys are mixtures of two or more elements, where at least one is a metal.

  • Example: Steel (Iron + Carbon).

  • Advantages:

    • Harder and stronger

    • More resistant to corrosion

    • Better electrical or thermal properties

  • Examples: Jewelry (gold alloys), aircraft parts (aluminum alloys).

  • Properties compared to pure metals:

    • Stronger: Brass vs. pure copper.

    • Lighter: Aluminum alloys in aircraft.

    • More Resistant: Stainless steel in wet environments.

  • Applications:

    • Everyday life: Coins, jewelry, kitchen utensils.

    • Industry: Aircraft, ships, and vehicles.

    • Medicine: Surgical tools, dental braces.

  • Fun Facts:

    • Gold jewelry is rarely pure gold; it's usually mixed with other metals for durability.