Question

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> How does ionisation energy vary along the period and down the group in s-block elements?Why does this variation occur?

Answer 1

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> i)Ionisation energy increases along the period from left to right and it decreases down the group.
ii) In a group there is increase of number shells and decrease of force of attraction of nucleus over the shells. So,the ionisation energy decrease down the group.
iii) Along the period, electrons are added to the same shell which iincreases the force of attraction of nucleus over the shell. So, ionisation energy increases alon the period from left to right.