Reactivity Series

Some metals like sodium is highly reactive. Sodium reacts vigorously even with cold water producing hydrogen. Some metals like iron is less reactive. Iron will get rust in the presence of water and air and it will take weeks. Some metals like gold is not reactive at all. Order of the reactivity of metals is very important to make predictions of their reactivities and several other information. When the metals are ordered according to their reactivities it is called ' reactivity series'.

Arranging the metals in the reactivity series has done looking at their reactivities such as reaction with air, water, displacement reactions etc.

Order of the metals in the reactivity series can be given as follows.

K (pottasium)
Na (Sodium)
Ca (Calcium)
Mg (Magnesium)
Al (Aluminium)
Zn(Zinc)
Fe(Iron)
Sn (Tin)
Pd( lead)
(H)-(Hydrogen)
Cu (Copper)
Hg( Mercury)
Ag (silver)
Au (gold)
Pt (platinum)

Reactivity decreases down the reactivity series.

Hydrogen is not a metal . It has been included in the reactivity series to compare the reactivity of metals.

Metals

Elements in the periodic table can be divided in to metals, non metals and metalloids having both metallic and non metallic characters.
All the transition elements and all the elements in the first two groups of the periodic table are among the metals found in the periodic table. Metals are mostly solids except for mercury (Hg) which is a liquid metal.

Metals can be identified by their metallic properties such as

•  having high melting points 
•  having high boiling points;
•  malleable
•  good conductors of heat 
•  good conductors of electricity

These properties of metals can be explained with the structure of the metals

Metals are making a giant structure with metallic ions (e.g : Cu 2+ ions in Cu, Na + ions in Na) bonded together tightly with each other with metallic bonds forming  a giant 3d structure. Delocalized free moving electrons are moving around the ion lattice.

High melting and boiling point of the metals are due to the strong metallic bonds found in metal structure due to the electrostatic force between positively charged metal ions and negatively charged free moving electrons.

Metals are malleable because the layers of metal ions can slide over each other without braking due to the free moving electrons acting like a glue.

Electrical and heat conductivity of metals is due to the free moving electrons passing the energy.

Properties of metals can be improved by making them in to alloys. alloys are a mixture of a metal with another element,
e.g. brass; stainless steel

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