It is written in NCERT that" the bonds formed by elements having bigger atoms are much weaker." so my question is how we will evaluate that which element's atom is bigger and which element's atom is smaller ?
Dear student
We can figure the atomic size of an element by looking at its atomic number and also its position in the periodic table.
Since we know, that in the same group, when we move down the group , only the new shells are added and the valence electrons remain the same, hence down the group atomic radius increases.
Whereas across the period, since electrons are added in the same shell so effective nuclear charge increases which in turn leads to reduction in atomic size.
For example, in group I containing alkali earth metals, H, Li, Na
atomic size of Na is bigger than Li so, NaCl bond is weaker than LiCl .
Regards
We can figure the atomic size of an element by looking at its atomic number and also its position in the periodic table.
Since we know, that in the same group, when we move down the group , only the new shells are added and the valence electrons remain the same, hence down the group atomic radius increases.
Whereas across the period, since electrons are added in the same shell so effective nuclear charge increases which in turn leads to reduction in atomic size.
For example, in group I containing alkali earth metals, H, Li, Na
atomic size of Na is bigger than Li so, NaCl bond is weaker than LiCl .
Regards