5. Write the equation involved in the following tests? + |Molisch test Mucic acid test Bials-orcinol test Seliwanoff's test

Reagents: 8 ml conc. Sulfuric acid, 1.5 ml alpha naphthol, 1 ml iodine in KI, 4 ml conc. HNO3, 4 ml Seliwanoff’s reagent, 3 ml Bial’s-orcinol reagent, SAMPLE: 5% of lactose, sucrose, glucose, galactose, fructose, maltose, starch and xylose ( 10 ml each) Materials: 12 test tubes 20 ml, test tube rack, test tube brush, test tube holder, alcohol lamp, tripod, wire gauze, water bath, (10 ml) graduated cylinder, dropper, stirring rod, 3 droppers, 250 ml beaker Procedure: 1. Molisch Test – (use all 8 samples) Place 1 ml of each sample in different test tubes. Add 1 drops of alpha napthol reagent in each tube. Mix thoroughly. Incline the tube and CAREFULLY allow 1 ml of conc. H2SO4 to flow down the side of the tube. Note the color formed at the zone of contact between 2 liquids. 2. Iodine Test – ( use all 8 samples) place 1 ml of the sample in a test tube. Add a drop of iodine. Observed color produced. Heat (direct heating) and note change in color. Cool and record again the result. 3. Mucic acid test – place 1 ml of the sample (lactose, galactose, glucose, fructose) in separate tubes. Add 1 ml conc. HNO3 in each tube. Heat the tubes in a boiling water bath for 1 hour. Cool at room temperature. Induce crystallization by scratching the side of the tube with a clean stirring rod, if no crystals appear; let it stand until the next laboratory period. Examine the crystals under the microscope and draw. 4. Seliwanoff’s test – prepare 4 test tubes and place 5 drops of glucose, fructose, sucrose and xylose in separate test tubes. Add 1 ml of seliwanoff’s reagent in each of the 4 test tubes. Immerse in a boiling water bath. Observe the color change in each tube after 3 minutes of boiling. If no color change is observed, continue heating for another 2 minutes and observe. 5. Bial’s-Orcinol test – place 5 drops each of the sugar solution (fructose, glucose and xylose) into a clean separate test tube. Add 1 ml of bial’s-orcinol reagent into each tube. Place the tubes in a boiling water bath. Note the color change during the 5 minutes of heating.