According to the Lewis formula of $O_3$,the correct option is

The number of $S-S$ bonds in $SO_3, S_2O_3^{2-}, S_2O_6^{2-}$ and $S_2O_8^{2-}$ respectively are

The ionization enthalpy of $Na^{+}$ formation from $Na_{(g)}$ is $495.8 \ kJ \ mol^{-1},$ while the electron gain enthalpy of $Br_{(g)}$ is $-325.0 \ kJ \ mol^{-1}$. Given the lattice enthalpy of $NaBr_{(s)}$ is $-728.4 \ kJ \ mol^{-1}$. The energy for the reaction $Na_{(g)} + Br_{(g)} \rightarrow NaBr_{(s)}$ is $(-) \dots \dots \dots \dots \dots \times 10^{-1} \ kJ \ mol^{-1}$.

Which of the following compounds contains both polar and non-polar bonds?

The correct order of increasing $C-O$ bond strength of $CO, CO_3^{2-}, CO_2$ is

The formation of a chemical bond is accompanied by