The s-Block Elements Test - 5

Washing soda is Na₂CO₃.10H₂O i.e. sodium carbonate decahydrate. It is used in water softening, laundering and cleaning, manufacture of glass etc.

Common salt is sodium chloride i.e. NaCl. It is generally obtained by evaporation of sea water. It is used as a table salt for domestic purposes.

Caustic Soda is Sodium hydroxide i.e. NaOH. Sodium hydroxide is generally prepared commercially by the electrolysis of sodium chloride in Castner-Kellner cell. It is used in the manufacture of soap.

Sodium hydrogen carbonate i.e. NaHCO₃ is baking soda because it decomposes on heating to generate bubbles of carbon dioxide (leaving holes in cakes or pastries and making them light and fluffy).

Potassium ions are the most abundant cations. They activate many enzymes and participate in the oxidation of glucose to produce ATP.

Alkaline earth metals have two electrons in the s-orbital of the valence shell. Their general electronic configuration may be represented as [noble gas] ns². So they lose 2 electrons to attain noble gas configuration.

The reason is that the atoms of alkali metals are of large sizes. therefore, the outermost electon is for away from the nucleus and canbe easily removed

As we move down the group size increases so IE value decreases thus electropositivity also decreases.( shielding effect also decreases as we go down the Group)

As we move down the group ionic radii increases.