The heat of combustion of solid benzoic acid at constant volume is $$-321.30 \mathrm{~kJ}$$ at $$27^{\circ} \mathrm{C}$$. The heat of combustion at constant pressure is $$(-321.30-x \mathrm{R}) \mathrm{~kJ}$$, the value of $$x$$ is __________.

In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is _______ BM (Nearest integer) [Given atomic number of $$\mathrm{Cu}=29, \mathrm{Ni}=28, \mathrm{Mn}=25, \mathrm{Fe}=26$$]

The number of halobenzenes from the following that can be prepared by Sandmeyer's reaction is _________

An artificial cell is made by encapsulating $$0.2 \mathrm{~M}$$ glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a $$0.05 \mathrm{~M}$$ solution of $$\mathrm{NaCl}$$ at $$300 \mathrm{~K}$$ is ________ $$\times 10^{-1}$$ bar. (nearest integer).

[Given : $$\mathrm{R}=0.083 \mathrm{~L} \mathrm{~bar} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$$ ]

Assume complete dissociation of $$\mathrm{NaCl}$$