How many moles of ammonium ions are in 6.945 g of ammonium carbonate?

Ammonium carbonate is a salt that is soluble and is made up of ammonium radicle and a carbonate radicle. If the salt ionizes; 
(NH4)2CO3 = 2NH4+   + CO3^-2, this means 1 mole of the salt contains two moles of ammonium ions.
1 mole of ammonium carbonate contains 96.0858 g
Therefore, 6.945 g are equivalent to (6.945/96.0858) = 0.07228 moles
Thus, 6.945 g of ammonium carbonate contains 2 × 0.07228 = 0.14456 moles.

The molar mass of a substance is defined as the mass of 1 mol of that substance, expressed in grams per mole, and is equal to the mass of 6.022 × 10 23 atoms, molecules, or formula units of that substance.

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