The mass of iron converted into Fe₃O₄ by the action of 18 g of steam is:

(Given: Molar mass of H, O and Fe are 1, 16 and 56 g mol⁻¹ respectively)

Assume iron is present in excess:

What is the energy (in J atom⁻¹) required for the following process?

Li²⁺ (g) → Li³⁺ (g) + e⁻

(Take the ionization energy for the H atom in the ground state as $2.18 \times 10^{−18} \text{ J atom}^{−1}$)

Given below are two statements :

Statement (I): The correct sequence of bond lengths in the following species is :

$\ce{O2^{+}} < \ce{O2} < \ce{O2^{-}} < \ce{O2^{2-}}$

Statement (II): The correct sequence of number of unpaired electrons in the following species is :

$\ce{O2} > \ce{O2^{+}} > \ce{O2^{-}} > \ce{O2^{2-}}$

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

Consider the following data.

(i) $2\text{Al(s)} + 6\text{HCl(aq)} \rightarrow \text{Al}_2\text{Cl}_6\text{(aq)} + 3\text{H}_2\text{(g)} + 1200~\text{kJ/mol}$

(ii) $\text{H}_2\text{(g)} + \text{Cl}_2\text{(g)} \rightarrow 2\text{HCl(g)} + 164~\text{kJ/mol}$

(iii) $\text{HCl(g)} + \text{aq} \rightarrow \text{HCl(aq)} + 83~\text{kJ/mol}$

(iv) $\text{Al}_2\text{Cl}_6\text{(s)} + \text{aq} \rightarrow \text{Al}_2\text{Cl}_6\text{(aq)} + 663~\text{kJ/mol}$

The enthalpy of formation of anhydrous solid $\text{Al}_2\text{Cl}_6$ is :