Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.

${}_{19}\mathrm{K},{ }_3\mathrm{Li},{ }_{11}\mathrm{Na},{ }_4\mathrm{Be}$

Which of these atoms has the smallest atomic radius?

Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with an explanation.

Which of the above elements has the highest metallic character?

Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with an explanation.

${}_6\mathrm{C}{,}_3\mathrm{Li}{,}_9\mathrm{F}{,}_7\mathrm{N}{,}_8\mathrm{O}$

Which of the above elements has the highest nonmetallic character?

Write the name and symbol of the element having the smallest size.

Write a short note on Mendeleev’s periodic law.