Difference between Metals and Non-Metals

Metals Non-Metals
1. Metals are placed on the left hand side of the periodic table. Non-metals are placed on the right hand side of the periodic table.
2. Metals lose electrons to become positive ions (Cations) e.g., N+, Mg2+ Non-metals gain electrons to become negative ions (Anions) e.g.Cl-, O2-
3. Metals are solid at room temperature except Mercury which is liquid. Non-metals may be solid (carbon, sulphur), liquid (Bromine), gaseous (chlorine, oxygen)(
4. Metals are strong (except Na, K) Non-metals are brittle
5. Metals have high melting and boiling points (except Na, K) Non-metals have low melting and boiling points (except diamond)
6.Metals have high densities (heavy elements) Non-metals have low densities (light elements)
7. Metals are malleable – drawn into sheets Non-metals are not malleable
8. Metals are ductile-can be drawn into wires. Non-metals are not ductile.
9. Metals are lustrous (shining) Non-metals are non-lustrous (except iodine)
10. Metals are sonorous Non-metals are non-sonorous
11. Metals are good conductors of heat (lead is poor conductor) Non-metals are bad conductors of heat
12. Metals are conduct electricity Non-metals cannot conduct electricity (except graphite)
13. Metals are hard (except Na and K can be cut with knife) Non-metals are soft (except diamond)

Occurrence of Metals in Nature

Calcination Roasting
  • It is done for carbonate ores.
  • It is done for sulphide ores.
  • Heating of carbonate ores in absence of oxygen.
  • Heating of sulphide ore in presence of oxygen.
  • Co2 gas is released and metal oxide in obtained.
  • SO2 gas is released and metal oxide is obtained.
  • ZnCO3(s) —heat–> ZnO(s) + CO2(g)
  • 2ZnS(s) + 3O2(g) –heat–> 2ZnO(s) + 2SO2(g)

Refining of Metals

To obtain pure metal, electrolytic refining of metals is done.

A strip of impure metal (to be refined) is taken as anode. Pure metal (small strip) of some material as cathode and electrolyte of same metal solution is used. Electric current is passed and all pure metal is obtained at cathode and impurities are collected at anode called as anode mud.


Metals when left open in air gets corroded.

i) Silver + Sulphur in air —-> Silver sulphide (black coat)

ii) Copper + Carbon dioxide in air —-> Copper carbonate (green coat)

iii) Iron + Air and moisture —> Iron, oxide, water molecules, rust (Brown flaky)

Prevention of Corrosion
  1. By applying paint
  2. By applying oil/grease
  3. Galvanizing a metal   —-> coating of zinc on metal
  4. Anodizing a metal      —-> coating a layer of aluminium oxide  (Al2O3)
  5. By making alloys        —-> Steel – (Fe + C)
    Brass – (Cu + Zn)
    Bronze – (Cu + Sn)