Time required for completion of $$99.9 \%$$ of a First order reaction is ________ times of half life $$\left(t_{1 / 2}\right)$$ of the reaction.

The hydrogen electrode is dipped in a solution of $$\mathrm{pH}=3$$ at $$25^{\circ} \mathrm{C}$$. The potential of the electrode will be _________ $$\times 10^{-2} \mathrm{~V}$$.

$$\left(\frac{2.303 \mathrm{RT}}{\mathrm{F}}=0.059 \mathrm{~V}\right)$$

The number of non-polar molecules from the following is _________. $$\mathrm{HF}, \mathrm{H}_2 \mathrm{O}, \mathrm{SO}_2, \mathrm{H}_2, \mathrm{CO}_2, \mathrm{CH}_4, \mathrm{NH}_3, \mathrm{HCl}, \mathrm{CHCl}_3, \mathrm{BF}_3$$

$$9.3 \mathrm{~g}$$ 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 $$\mathrm{g} \mathrm{~mol}^{-1}$$

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