A gas (Molar mass = 280 $$\mathrm{~g} \mathrm{~mol}^{-1}$$) was burnt in excess $$\mathrm{O}_{2}$$ in a constant volume calorimeter and during combustion the temperature of calorimeter increased from $$298.0 \mathrm{~K}$$ to $$298.45$$ $$\mathrm{K}$$. If the heat capacity of calorimeter is $$2.5 \mathrm{~kJ} \mathrm{~K}^{-1}$$ and enthalpy of combustion of gas is $$9 \mathrm{~kJ} \mathrm{~mol}^{-1}$$ then amount of gas burnt is _____________ g. (Nearest Integer)

When a certain amount of solid A is dissolved in $$100 \mathrm{~g}$$ of water at $$25^{\circ} \mathrm{C}$$ to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is $$23.76 \,\mathrm{mmHg}$$. The number of moles of solute A added is _____________. (Nearest Integer)

$$\matrix{ {[A]} & \to & {[B]} \cr {{\mathop{\rm Reactant}\nolimits} } & {} & {{\mathop{\rm Product}\nolimits} } \cr } $$

If formation of compound $$[\mathrm{B}]$$ follows the first order of kinetics and after 70 minutes the concentration of $$[\mathrm{A}]$$ was found to be half of its initial concentration. Then the rate constant of the reaction is $$x \times 10^{-6} \mathrm{~s}^{-1}$$. The value of $$x$$ is ______________. (Nearest Integer)

The number of molecule(s) or ion(s) from the following having non-planar structure is ____________.

$$\mathrm{NO}_{3}^{-}, \mathrm{H}_{2} \mathrm{O}_{2}, \mathrm{BF}_{3}, \mathrm{PCl}_{3}, \mathrm{XeF}_{4}, \mathrm{SF}_{4}, \mathrm{XeO}_{3}, \mathrm{PH}_{4}^{+}, \mathrm{SO}_{3},\left[\mathrm{Al}(\mathrm{OH})_{4}\right]^{-}$$