Given below are two statements :

Statement I : The number of pairs among $\left[\mathrm{Al}_2 \mathrm{O}_3, \mathrm{Cr}_2 \mathrm{O}_3\right],\left[\mathrm{Cl}_2 \mathrm{O}_7, \mathrm{Mn}_2 \mathrm{O}_7\right],\left[\mathrm{Na}_2 \mathrm{O}, \mathrm{V}_2 \mathrm{O}_3\right]$ and $\left[\mathrm{CO}, \mathrm{N}_2 \mathrm{O}\right]$ that contain oxides of same nature (acidic, basic, neutral or amphoteric) is 4 .

Statement II : Among $\mathrm{Na}_2 \mathrm{O}, \mathrm{Al}_2 \mathrm{O}_3, \mathrm{CO}$ and $\mathrm{Cl}_2 \mathrm{O}_7$, the most basic and acidic oxides are $\mathrm{Na}_2 \mathrm{O}$ and $\mathrm{Cl}_2 \mathrm{O}_7$, respectively.

In the light of the above statements, choose the correct answer from the options given below :

Given below are two statements:

Statement I: The correct order of electronegativity of fluorine, oxygen and nitrogen is $\mathrm{F}>\mathrm{O}>\mathrm{N}$.

Statement II: The oxidation state of oxygen in $\mathrm{OF}_2$ is +2 and in $\mathrm{Na}_2 \mathrm{O}$ is -2 .

In the light of the above statements, choose the correct answer from the options given below

The $1^{\text {st }}$ ionization enthalpy for Mg is $+737 \mathrm{~kJ} / \mathrm{mol}$. The most probable estimated value of the $2^{\text {nd }}$ ionization enthalpy of Mg is $\_\_\_\_$ .

The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is :