Water formula for

An acid can be described as a substance that yields hydrogen ions (W ) when dissolved in water. Formulas for acids contain one or more hydrogen atoms as well as an anionic group. Anions whose names end in -ide form acids with a hydro- prefix and an -ic ending, as shown in Table 2.5. In some cases two different names seem to be assigned to the same chemical formula. 

Formulas for hydrates are expressed by first writing the usual anhydrous (without water) formula for the compound and then adding a dot followed by the number of water... 

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