Metals: Properties and reactivity series
There are 118 elements known at present. There are similarities as well as differences are the properties of these elements on the basis of their, all the element can be divided three types: Metal; non- Metal; metalloid Metals are those elements which losses electrons and provides cation. In the periodic table, these elements are located and confined towards left and middle. Also the elements which are located extremely left have most metallic properties.
Physical properties of Metals
- They are good conductor of heat and electricity and are malleable and ductile.
- They have lustre.
- They are heavy and sonorous.
- These elements form positive ions by loosing electrons (or donating).
- Aluminium, Iron, Calcium, Sodium, Potassium, and Magnesium are the major metals is found abundance in the earth’s crust (names are in decreasing order)
- They are solid at room temperature (Except Mercury).
- They have high melting and boiling points (except Sodium and potassium).
- They have high densities (except Sodium and Potassium).
Chemical properties of Metals
Metals are very reactive and tend to losses electrons easily and form positively charged ions; therefore metals are called electropositive elements. Sodium metal forms sodium ions Na+, Mg forms positively charged Magnesium ions Mg2+and aluminium forms aluminium ions Al3+. The electropositive nature allows metals to form compounds with other elements easily. The chemical metal chemical properties of metals are discussed below:
Reaction of Metals with Oxygen: When metal are burnt in air, they react with the oxygen to form metal oxide. For Example –
Reaction of Metals with Water: Metals react with water to form a metal hydroxide and Hydrogen gas. For Example-
Reaction of Metals with Acids: Metals are usually displace hydrogen from dilute acids (Except copper, silver and gold do not displace hydrogen from dilutes acid because they are less reactive than other metals). For Example-
Reaction of Metals with Salt Solutions: Reactive metals can displace any metal less reactive than itself, from the oxide, chloride or sulphate of the less reactive metal in solution or their molten state. If metal A displaces metal B from its solution, it is more reactive than B.
The reactivity series of metal
In the reactivity series, the most reactive metal is placed at the top whereas the least reactive metal is placed at the bottom.
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