S P Singh Solutions for Chapter: Periodic Table, Periodic Properties and Variations of Properties, Exercise 2: Intext Questions

Explain why the following statement is not correct.

Atoms of elements in the same group have the same number of electron(s).

Explain why the following statement is not correct.

Non-metallic character decreases across a period with the increase in atomic number.

Explain why the following statement is not correct.

Reactivity increases with atomic number in a group as well as in a period.

State the number of elements in Period $\mathrm{I}$, Period $\mathrm{II}$, and Period $\mathrm{III}$ of the periodic table. Name them.

What is the common feature of the electronic configuration of the elements at the end of Period $\mathrm{II}$ and Period $\mathrm{III}$.

Give reasons for the following:

The size of a ${\mathrm{Cl}}^{-}$ ion is greater than the size of a $\mathrm{Cl}$ atom.

Give reasons for the following:

Give reasons for the following:

Ionisation potential of the element increases across a period.