Carbohydrates Monosaccharides properties

note on properties

1. MONOSACCHARIDES – PROPERTIES Dr. V. RAMESH Assistant Professor & Head In-Charge, Department of Botany, Vivekananda College, Tiruvedakam West – 625 234 Madurai.

2. PROPERTISE OF MONOSACCHARIDES Physical properties I . Colour and Shape - Colourless, crystalline. II. Solubility - soluble in water and alcohol in soluble in ether III. Taste - Sweet taste IV. Optical activity They are optically active . They may rotate the light either right or left . Dextrorotatory or D – Form - rotate the light in right or clockwise direction. Levorotatory or L- Form - rotate the light in left or anti clockwise direction

3. iv. Mutarotation Chang in specific rotation of an optically active compound is called mutarotaiton. When a monosaccharide's are dissolved in water, the optical rotation gradually changes until It reaches a constant values Fresh aqueous solution of α –D-Glucose specific rotation – 112.2° Standing …………….. – 52.7 ° 112.2° - 52.7 ° = 59.5 ° Mutarotation of α –D-Glucose is 59.5 °

4. CHEMICAL PROPERTIES I. OXIDATION Monosaccharides ---------- Gluconic acid Ag 2 O ( Tollens reagent) 2Cu(OH) 2 Fehling Solution

5. II.REDUCTION Monosaccharides ---------- Sugar Alchols Sodium amalgam

6. THANK YOU