Due to catenation property of carbon it is able to form a large number of compounds. To study those compounds, we have classified them as organic compound. The previous definition of organic compound was that the compounds which are obtained from living organism. However after Wholer's synthesis (synthesis of urea from inorganic material) the definition was changed.
so in modern world of chemistry, KeKule (who described the ring structure of benzene) will considered to be an organic chemist as he studied organic compound.
for sugar to dissolve in water hydaration must be equal to or greater than the lattice energy or molecular forces so when the molecular forces breaks new atoms are formed for recombination in new compound
