Difference between the alkaline metals and …

Properties

Alkaline earth metals

Alkali metals

1.

Physical properties

Comparatively harder. High melting points. Diamagnetic.

Soft, low melting points paramagnetic.

2.

Valency

Bivalent

Monovalent

3.

Electropositive nature

Less electropositive

More electropositive

4.

Hydroxides

Weak bases, less soluble and decompose on heating.

Strong bases, highly soluble and stable towards heat.

5.

Bicarbonates

These are not known in free state. Exist only in solution.

These are known in solid state.

6.

Carbonates

Insoluble in water. Decompose on heating.

Soluble in water. Do not decompose on heating (LiCO3 is an exception)

7.

Action of carbon

Directly combine with carbon and form carbides

Do not directly combine with carbon

8.

Solubility of salts

Sulphates, phosphates fluorides, chromates, oxalates etc are insoluble in water

Sulphates, phosphates, fluorides, chromates, oxides etc are soluble in water.

9.

Reducing power

Weaker as ionization potential values are high and oxidation potential values are low.

Stronger as ionization potential values are low and oxidation potential values are high

10.

Electronic configuration

Two electrons are present in the valency shall. The configuration is ns2 (bivalent)

One electron is present in the valency shell. The configuration is ns1 (monovalent) more electropositive