Oxalic Acid 144-62-7
Oxalic acid is an organic compound that occurs in many types of plants, e.g. (sorrel and rhubarb). It is obtained by heating sodium formate to a temperature of approx. 400 ° C , resulting in the formation of sodium oxalate, which is then converted into oxalic acid with dilute sulfuric acid. Oxalic acid is used, among others, to remove rust, remove ink stains and in dyes and powders for cleaning sanitary equipment. In high concentrations, oxalic acid irritates the skin and mucous membranes are deposited in the form of stones in the kidneys. Therefore, frequent consumption of large amounts of vegetables containing this acid can cause kidney stones as well as calcium deficiency in the body
Density: 1.900 g / cm³ (17 ° C, anhydrous) ; solid
Water solubility: 95.2 g / kg (20 ° C, anhydrous) 
Melting point: 101.5 ° C (dihydrate)
Sublimation temperature: 157 ° C (anhydrous) [2
Decomposition temperature: 189.5 ° C
Acidity: pKa1 1.25; pKa2 3.81 [3
Labels for hazardous chemicals and mixtures that are part of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). The pictograms recommended by GHS have the shape of a square set on the top. They should contain a black symbol on a white background with a red border.
Priority rules to be observed in connection with the labeling of a substance:
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Source: GHS pictograms