i) No. of electron in ONF = 24 No. of electron in ${NO_2^{-} = 24$ both are isoelectronic (ii) ${OF_2}$ is a fluoride of oxygen not oxide of fluorine because EN of fluorine is more than oxygen ${OF_2}$ = oxygen difluoride (iii) ${Cl_2O_7}$ is an anhydride of perchloric acid ${2HClO_4 ->[\Delta][-H_2O] Cl_2 O_7}$ (iv) ${O_3} $ molecule is bent
P block elements are those in which the last electron enters any of the three p-orbitals of their respective shells. Since a p-subshell has three degenerate p-orbitals each of which can accommodate two electrons, therefore in all there are six groups of p-block elements.
P block elements are shiny and usually a good conductor of electricity and heat as they have a tendency to lose an electron. You will find some amazing properties of elements in a P-block element like gallium. It’s a metal that can melt in the palm of your hand. Silicon is also one of the most important metalloids of the p-block group as it is an important component of glass.