The correct order of bond length is:

How many lone pairs of electrons are present in a hydroxyl ion?

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 $(-) \dots \dots \dots \dots \dots \times 10^{-1} \ kJ \ mol^{-1}$.

$O-O$ bond length in $H_2O_2$ is $\underline{X}$ than the $O-O$ bond length in $F_2O_2$. The $O-H$ bond length in $H_2O_2$ is $Y$ than that of the $O-F$ bond in $F_2O_2$. Choose the correct option for $\underline{X}$ and $\underline{Y}$ from the given below.

The set of molecules in which the central atom does not obey the octet rule is

Which of the following statements is incorrect?