biomolecules

organic; ratofy.

acetic acid

(CH3COOH); carbohydrate exception; same gen formula

rhamnose

C6H12O5; carbohydrate. diff formula

sucrose

common; present in homes

lactose

milk

monosaccharides

glucose, fructose, ribose.

sucrose(hydrolysis)

glucose+fructose

maltose(hydrolysis)

glucose+glucose

polysaccharides

starch, cellulose, glycogen, gums, etc.

non sugars

polysaccharrides, not sweet

fact about monosaccharides

reducing

condition for reucing sugar: disac

free aldehydic or ketonic group; maltose or lactose

non reducing disac

sucrose

prep of glucose (i)

from sucrose; boiling; h2so4 or dil HCl; gives glucose+fructose

commercial method

obtained by hydrolysis of starch OR cellulose by boiling it with dilute H2SO4 at 393 K under pressure 2-3 atm.

aldohexose

dextrose; glucose

structure; heating

On prolonged heating with HI, it forms n-hexane, suggesting that all the six carbon atoms are linked in a straight chain.

Cyclic Structure of Glucose

Schiffs test; NaHSO3

cyclic structure

The pentaacetate of glucose does not react with hydroxylamine indicating the absence of free —CHO group.

alpha glucose

The α-form of glucose (m.p. 419 K) is obtained by crystallisation from concentrated solution of glucose at 303 K

beta glucose

(m.p. 423 K) is obtained by crystallisation from hot and saturated aqueous solution at 371 K.