arrange in increasing order of atomic sizes
li ,be , b , c, n , o, f ,ne, .
Li, Be, B, C, N, O, F, Ne belongs to same period (2nd period). We know size of atom decreases as we move from left to right in a period (because number of proton increases, so effective nuclear charge increases which attract electrons more strongly and size decreases). So atomic size decreases from Li to F. But Ne have larger size than F. This is because the atomic size of inert gas is actually van der Waal’s radius. Van der Waal attraction force is very weak compared to covalent attraction force of other elements. Thus atomic radius of inert gas is larger than halogens.
So atomic size is in the following order:
F<O<N<C<B<Be<Li and Ne have higher size than F.
So atomic size is in the following order:
F<O<N<C<B<Be<Li and Ne have higher size than F.