Question

HCL and hn O3 show acidic characteristics in aqua solution while alcohol and glucose solution do not give reason

Answer 1

HCl and HNO3 are strong acids (polar in nature) thus releases H+ ions when dissolved in aqueous solutions where as glucose and alcohol molecules are not acids (and non polar in nature) so, they cannot release H+ ions in aqueous solutions. Alcohols partially release H+ ions in aqueous solutions, so they are considered as weak acids. 

Answer 2

It is just of because the they give H+ in aq. solution and glucose and alchol so not give H+ in aq. solution.