A metal surface of $$100 \mathrm{~cm}^{2}$$ area has to be coated with nickel layer of thickness $$0.001 \mathrm{~mm}$$. A current of $$2 \mathrm{~A}$$ was passed through a solution of $$\mathrm{Ni}\left(\mathrm{NO}_{3}\right)_{2}$$ for '$$\mathrm{x}$$' seconds to coat the desired layer. The value of $$\mathrm{x}$$ is __________. (Nearest integer) ( $$\rho_{\mathrm{Ni}}$$ (density of Nickel) is $$10 \mathrm{~g} \mathrm{~mL}$$, Molar mass of Nickel is $$60 \mathrm{~g} \mathrm{~mol}^{-1}$$ $$\left.\mathrm{F}=96500 ~\mathrm{C} ~\mathrm{mol}^{-1}\right)$$

A certain quantity of real gas occupies a volume of $$0.15~ \mathrm{dm}^{3}$$ at $$100 \mathrm{~atm}$$ and $$500 \mathrm{~K}$$ when its compressibility factor is 1.07 . Its volume at 300 atm and $$300 \mathrm{~K}$$ (When its compressibility factor is 1.4 ) is ___________ $$\times 10^{-4} ~\mathrm{dm}^{3}$$ (Nearest integer)

$$\mathrm{A}_{2}+\mathrm{B}_{2} \rightarrow 2 \mathrm{AB} . \Delta H_{f}^{0}=-200 \mathrm{~kJ} \mathrm{~mol}^{-1}$$

$$\mathrm{AB}, \mathrm{A}_{2}$$ and $$\mathrm{B}_{2}$$ are diatomic molecules. If the bond enthalpies of $$\mathrm{A}_{2}, \mathrm{~B}_{2}$$ and $$\mathrm{AB}$$ are in the ratio $$1: 0.5: 1$$, then the bond enthalpy of $$\mathrm{A}_{2}$$ is ____________ $$\mathrm{kJ} ~\mathrm{mol}^{-1}$$ (Nearest integer)

$$25.0 \mathrm{~mL}$$ of $$0.050 ~\mathrm{M} ~\mathrm{Ba}\left(\mathrm{NO}_{3}\right)_{2}$$ is mixed with $$25.0 \mathrm{~mL}$$ of $$0.020 ~\mathrm{M} ~\mathrm{NaF} . \mathrm{K}_{\mathrm{Sp}}$$ of $$\mathrm{BaF}_{2}$$ is $$0.5 \times 10^{-6}$$ at $$298 \mathrm{~K}$$. The ratio of $$\left[\mathrm{Ba}^{2+}\right]\left[\mathrm{F}^{-}\right]^{2}$$ and $$\mathrm{K}_{\mathrm{sp}}$$ is ___________.

(Nearest integer)