The number of units, which are used to express concentration of solutions from the following is _________

Mass percent, Mole, Mole fraction, Molarity, ppm, Molality

When $$\mathrm{Fe_{0.93}O}$$ is heated in presence of oxygen, it converts to $$\mathrm{Fe_2O_3}$$. The number of correct statement/s from the following is ________

A. The equivalent weight of $$\mathrm{Fe_{0.93}O}$$ is $${{\mathrm{Molecular\,weight}} \over {0.79}}$$

B. The number of moles of Fe$$^{2+}$$ and Fe$$^{3+}$$ in 1 mole of $$\mathrm{Fe_{0.93}O}$$ is 0.79 and 0.14 respectively

C. $$\mathrm{Fe_{0.93}O}$$ is metal deficient with lattice comprising of cubic closed packed arrangement of O$$^{2-}$$ ions

D. The % composition of Fe$$^{2+}$$ and Fe$$^{3+}$$ in $$\mathrm{Fe_{0.93}O}$$ is 85% and 15% respectively

5 g of NaOH was dissolved in deionized water to prepare a 450 mL stock solution. What volume (in mL) of this solution would be required to prepare 500 mL of 0.1 M solution? _____________

Given : Molar Mass of Na, O and H is 23, 16 and 1 g mol$$^{-1}$$ respectively

A 1.84 mg sample of polyhydric alcoholic compound 'X' of molar mass 92.0 g/mol gave 1.344 mL of $$\mathrm{H}_{2}$$ gas at STP. The number of alcoholic hydrogens present in compound 'X' is ________.