Phosphorous Acid, A balancing of a phosphite (a salt of phosphorous acid) and three hydrogen's to achieve net neutrality.

what is the amu of phosphoric acid

The symbol for the element phosphorus is P. Phosphorous is not the name of an element but rather of an acid, H3PO3.

H3PO3 is phosphorous acid or orthophosphorous acid. It is a colorless or yellowish solid with a garlic like taste. It is an unstable compound that readily absorbs moisture and converts to phosphoric acid (H3PO4).

H₃PO₃ is the molecular formula for Phosphorus Acid.

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