When a hydrated salt,$Na_2SO_4 \cdot nH_2O$,is heated,it loses $56\%$ of its weight and becomes anhydrous. What is the approximate value of $n$?

What are the active masses of methyl alcohol $(CH_3OH)$ and carbon tetrachloride $(CCl_4)$ respectively,if their densities are $0.5 \, g/mL$ and $1.3 \, g/mL$?

At $27\,^oC$,for the reaction,$N_2O_{4(g)} \to 2NO_{2(g)}$,the rate of reaction is $6 \times 10^{-3} \, atm \, min^{-1}$. Find the rate of the same reaction in terms of $mol \, L^{-1} \, min^{-1}$.

Mass of magnesium required to produce $220 \ mL$ of hydrogen gas at $STP$ on reaction with excess of dil. $HCl$ is (Given: Molar mass of $Mg$ is $24 \ g \ mol^{-1}$)

Haemoglobin contains $0.33\%$ of iron by weight. The molecular weight of haemoglobin is approximately $67200$. The number of iron atoms (At. wt. of $Fe = 56$) present in one molecule of haemoglobin is

What is the molarity of $H_2SO_4$ solution if $25 \ mL$ is exactly neutralized with $32.63 \ mL$ of $0.164 \ M$ $NaOH$ (in $M$)?