Question

Which are true statements about s-block elements?

• A. Metals are obtained by the electrolytic of fused chlorides.
• B. Oxides are basic except BeO
• C. +1 valency by alkali metals and +2 valency alkaline earth metals is shown
• D. carbonates are thermally stable

Answer 1

Answer: (A), (B), (C)

The correct options are
A Metals are obtained by the electrolytic of fused chlorides.
B Oxides are basic except BeO
C +1 valency by alkali metals and +2 valency alkaline earth metals is shown

Carbonated of all alkali metals are not thermally stable.
Ca and Li carbonate decomposes into their oxides on heating.
Ca bicarbonate on heating forms Ca cabonate which further decomposes into oxide and cabon dioxide.
Only sodium carbonate is thermally stable.
Electronic configuration of alkali metals is - $n{s}^1$ so they have +1 valency.
Electronic configuration of alkaline earth metals is $n{s}^2$ so they have +2 valency.