Content text CARBOHYDRATES.pdf
CARBOHYDRATES COMMON NAMES: SUGARS Because more familiar carbohydrates have sweet taste. SACCHARIDES From GREEK word SAKCHARON which means sugars COMPOSITION: Carbon, Hydrogen, Oxygen OLD CONCEPT: The name carbohydrates mean. HYDRATES OF CARBON in which hydrogen and oxygen is present in the same ratio as in water 2:1, but now many carbohydrates are known to contain hydrogen and oxygen in different proportions. COMPOUNDS THAT OBEY THIS CONCEPT... Glucose (CC6HH12OO6) Sucrose (CC12HH22OO11) Starch and cellulose (CC6HH10OO5)n (FROM FEDERAL BOOK) eprepare.org
COMPOUNDS THAT DONOT OBEY Rhamnose (CC6HH12OO5)n (FROM FEDERAL BOOK) MODERN CONCEPT: DEFINITION: Carbohydrates are POLYHYDROXY ALDEHYDES or KETONES or substances which yield such compounds on hydrolysis. CLASSIFICATION OF CARBOHYDRATES: Table Taken from Federal Book eprepare.org
MONOSACCHARIDES WORD STUDY: MONO=ONE , SACCHARUM=SUGAR MAIN POINTS: Empirical Formula of monosaccharides is (CCHH22OO)nn Monosaccharides are WHITE CRYSTALLINE POWDER Number of carbon atoms in monosaccharides ranges from 3-7 They have names which end in –ose MONOSACCHARIDES NO. OF CARBON ATOMS EXAMPLES FUNCTIONAL GROUPS TRIOSES 3C GLYCERALDEHYDE ALDEHYDE GROUP PENTOSES 5C RIBOSE ALDEHYDE GROUP RIBULOSE KETONIC GROUP HEXOSES 6C GLUCOSE ALDEHYDE GROUP FRUCTOSE KETONIC GROUP GALACTOSE ALDEHYDE GROUP SIMPLEST CARBOHYDRATE=MONOSACCHARIDES SIMPLEST MONOSACCHARIDES= TRIOSES eprepare.org 5C 6C 6C
(GLYCERIN)(TRIOSE) ISOMERS: DEFINITION: Compounds having SAME EMPIRICAL FORMULA but DIFFERENT STRUCTURES EXAMPLES: Glucose, Fructose, Galactose NOTE: Dear students, must memorize these structures as they are part of textbook. Ribose GLYCERALDEHYDE GLUCOSE (Chain Form) FRUCTOSE GLUCOSE (RING Form) Pentose eprepare.org
ISOMERS ARE INTERCONVERTIBLE. isomers contain the same number of atoms for each element. the atomic arrangement differs. Despite having the same molecular formula, the physical properties of each molecule may differ, particularly if the functional groups associated with each molecule are different. EXTRA POINTS FROM FEDERAL BOOK: TRUE CARBOHYDRATES: Monosaccharides are true carbohydrates. ALDOSES: Monosaccharides containing aldehyde group are called aldoses. KETOSES: Monosaccharides containing ketonic group are called ketoses. eprepare.org