Aqueous HCl reacts with MnO₂(s) to form MnCl₂(aq), Cl₂(g), and H₂O(l). What is the weight (in g) of Cl₂ liberated when 8.7 g of MnO₂(s) is reacted with excess aqueous HCl solution? (Given Molar mass in g mol⁻¹ Mn = 55, Cl = 35.5, O = 16, H = 1)

Identify the metal ions among $\mathrm{Co^{2+}}$, $\mathrm{Ni^{2+}}$, $\mathrm{Fe^{2+}}$, $\mathrm{V^{3+}}$ and $\mathrm{Ti^{2+}}$ having a spin-only magnetic moment value more than 3.0 BM. The sum of unpaired electrons present in the high spin octahedral complexes formed by those metal ions is _________ .

The osmotic pressure of a living cell is 12 atm at 300 K. The strength of sodium chloride solution that is isotonic with the living cell at this temperature is ________ g L^-1. (Nearest integer)

Given : R = 0.08 L atm K^-1 mol^-1

Assume complete dissociation of NaCl

(Given: Molar mass of Na and Cl are 23 and 35.5 g mol^-1 respectively.)

The first and second ionization constants of H₂X are $2.5 \times 10^{-8}$ and $1.0 \times 10^{-13}$ respectively.

The concentration of ${X^{2-}}$ in $0.1\ \mathrm{M}$ H₂X solution is ______ $\times 10^{-15}\ \mathrm{M}$. (Nearest Integer)