BK'S LAW OF PREPARATION

Sucrose on hydrolysis gives (a) Two molecules of glulcose (b) Two molecules of fructose (c) One molecule each of glucose                       and fructose (d) One molecule each of glucose                       and mannose Which of the following is a disaccharide (a) Lactose (b) Starch (c) Cellulose (d) Glucose Glucose cannot be classified as (a) A hexose (b)A carbohydrate (c) An oligosaccharide (d)An aldose The reagent which forms crystalline osazone derivative when reacted with glucose, is (a) Fehling solution         (b) Phenylhydrazine (c) Benedict solution (d) Hydroxylamine An enzyme which brings about the conversion of starch into maltose is known as (a) Maltase (b) Zymase (c) Invertase (d) Diastase Canesugar on hydrolysis gives (a) Glucose and maltose (b) Glucose and lactose (c) Glucose and fructose (d) Only glucose Glucose is a (a) Monosaccharide (b) Disaccharide (c) Trisaccharide (d) Po

Gattermann-koch aldehyde synthesis : Benzene(C6H6) is converted into benzaldehyde by passing a mixture of carbon monoxide(CO) and HYDROCHLORIC ACID (HCl) gas under high pressure into the ether solution of benzene in presence of anhydrous aluminium chloride (AlCl3)and cuprous chloride CuCl2.

Stephen Aldehyde Synthesis When we convert  cyanides into aldehydes  by a method of  partial reduction  in presence of   SnCl 2 /HCl,  which is followed by  hydrolysis , is called as  Stephens aldehyde synthesis Stephen aldehyde synthesis  was first used by  Henry Stephen . This reaction used for preparation of  aldehydes  (R-CHO) from  nitriles  (R-CN) using  tinchloride  (SnCl 2 ) and  hydrochloric acid  (HCl). This reaction is more useful  when aromatic nitriles are used but not for all aromatic nitriles.