Question

What are the common physical & chemical properties of alkali metals?

Answer 1

Hint: Alkali Metals are the chemical compounds which belong to the s-block of the periodic table. They have the largest sizes in a particular period in the periodic table. Some of the examples of alkali metals are- Lithium (Li), Sodium (Na), Potassium (K) etc.

Complete step-by-step answer:
Alkali metals contain the following properties such as -
- They are shiny and soft.
- They are very reactive at high temperatures and pressures.
- They have a low density when compared to other metals.
- They are the good conductors of electricity and heat.

Common Physical features of alkali metals are -
- They can be easily cut (soft).
- They are light in color.
- Due to their large atomic size, they have low density.
- They have low melting & boiling point due to weak metallic bonding.

Common Chemical Features of alkali metals are-
- They are highly reactive due to their low ionization enthalpy.
- Their reaction with water leads to the formation of respective oxides or hydroxides.
- They are strong reducing agents.

Alkaline Earth metals - These are the chemical compounds that belong to the s-block of the periodic table but with very similar physical & chemical properties such as -
- Shiny, silvery- white
- Low boiling point
- Low melting point

Note - Best properties of Alkali metals are that there are different alkali metals that burn with different colored flames. For Eg- Sodium (orange yellow), Lithium (red), Rubidium (red) & Cesium (blue or violet). When moving down the periodic table. Each alkali metal shows properties such as Increased atomic radius, decreased electronegativity and decreased melting & boiling points.