A solution of $$\mathrm{H}_2 \mathrm{SO}_4$$ is $$31.4 \% \mathrm{H}_2 \mathrm{SO}_4$$ by mass and has a density of $$1.25 \mathrm{~g} / \mathrm{mL}$$. The molarity of the $$\mathrm{H}_2 \mathrm{SO}_4$$ solution is _________ $$\mathrm{M}$$ (nearest integer)

[Given molar mass of $$\mathrm{H}_2 \mathrm{SO}_4=98 \mathrm{~g} \mathrm{~mol}^{-1}$$]

$$9.3 \mathrm{~g}$$ of aniline is subjected to reaction with excess of acetic anhydride to prepare acetanilide. The mass of acetanilide produced if the reaction is $$100 \%$$ completed is _________ $$\times 10^{-1} \mathrm{~g}$$.

(Given molar mass in $$\mathrm{g} \mathrm{~mol}^{-1}$$

$$\begin{aligned} & \mathrm{N}: 14, \mathrm{O}: 16, \\ & \mathrm{C}: 12, \mathrm{H}: 1 \text { ) } \end{aligned}$$

Volume of $$3 \mathrm{M} \mathrm{~NaOH}$$ (formula weight $$40 \mathrm{~g} \mathrm{~mol}^{-1}$$ ) which can be prepared from $$84 \mathrm{~g}$$ of $$\mathrm{NaOH}$$ is __________ $$\times 10^{-1} \mathrm{dm}^3$$.

Mass of methane required to produce $$22 \mathrm{~g}$$ of $$\mathrm{CO}_2$$ after complete combustion is _______ g.

(Given Molar mass in g mol-1 $$\mathrm{C}=12.0$$, $$\mathrm{H}=1.0$$, $$\mathrm{O}=16.0)$$