KAl(SO4)2 · 12Н2O – potassium aluminum sulfate – exists in the form of highly-soluble white crystals. It is also known as potassium alum or potash alum. Potassium alum is used in medicine as a hemostatic (or styptic) and antiseptic. For instance, it is used to make special styptic pencils, which are used to alleviate pain from stings and bites and to reduce bleeding from small cuts, abrasions, and nosebleeds. Potassium alum is also an active compound in some antiperspirants and deodorants known as “crystal deodorants,” as it eliminates bacteria responsible for the odor of sweat. It is also used to purify water for drinking and industrial processes. When potassium alum crystals are added to water, any pollutant particles begin to stick together and form a precipitate, which is then easily filtered out.
This reagent is considered nonhazardous according to GHS classifications. Treat all reagents with caution.
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