In the reaction $LiH + AlH_3 \to LiAlH_4$,$AlH_3$ and $LiH$ act as:

Fill in the blanks given below:
$(i)$ The two theories based on the principles of quantum mechanics are ........ and ......... .
$(ii)$ The electronic configuration of carbon in the excited state is ........... .
$(iii)$ Through the combination of atomic orbitals,....... are formed.
$(iv)$ The ${\rm{CH}}_4$ molecule has a .......... shape.

Which of the following order of given properties is incorrect?

Find the correct option regarding the given chemical properties.

Write Lewis dot symbols for atoms of the following elements: $Mg$,$Na$,$B$,$O$,$N$,$Br$.

Which of the following pairs are isoelectronic and isostructural: $NO_3^-$,$CO_3^{2-}$,$ClO_3^-$,$SO_3$?