2-1.2.6Melting point About 190°CResidual on ignition =0.1% Impurity E =0.2% Heavy metals =10 ppm Copper =5ppm Iron =2ppm %Ascorbic acid (vitamin C) is a water-soluble vitamin. It occurs as a white or slightly yellow crystal or powder with a slight acidic taste. It is an antiscorbutic productAscorbic acid: Vitamin C, an essential nutrient found mainly in fruits and vegetables.