Compare the stability of a neutral sodium atom and a positive sodium ion. Justify your answer.

The electronic configuration of element X is $2, 8, 8, 1$ and the electronic configuration of element Y is $2, 8, 7$. Then the type of bond formed between these two elements is

Draw the electron dot diagram for the compound given below. Represent the electrons by (.) and (x) in the diagram.

• Calcium oxide [Atomic No. of $\mathrm{Ca}=20$ and $\mathrm{O}=8$]

The following table represents the elements and the atomic number. With reference to this, answer the following using only the alphabets given in the table.

Name the element which forms an ionic compound with chlorine.

What should be the correct order of lattice energy values of the following alkali halides?

$\mathrm{LiCl},\mathrm{KI},\mathrm{KCl}$and $\mathrm{NaCl}$

For the molecules $\mathrm{LiF},{\mathrm{N}}_2,{ \mathrm{K}}_2\mathrm{O}$ and ${\mathrm{ClF}}_3,$ what is the correct arrangement of bonds in order of increasing ionic character?