Calculate the concentration of an aqueous solution of non electrolyte at 300 K if its osmotic pressure is 12 atm .

$$ \left[\mathrm{R}=0.0821 \mathrm{~atm} \mathrm{dm}^3 \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right] $$

Which from following compounds is least soluble in water at STP?

Which of the following statements is correct about $\mathrm{O}_2$ and $\mathrm{O}_3$ molecule?

What is the total number of donor atoms present in Tetracyanonickelate(II) ion?