How many moles of ammonium ions are in 6.955 g of ammonium carbonate

The formula of ammonium carbonate is (NH4)2CO3

so as shown in the formula there are two moles of ammonium ion in each mole of ammonium carbonate .

Given : mass of ammonium carbonate = 6.955g

Molar mass of ammonium carbonate = 96 g / mol

Moles = mass / molar mass = 6.955 / 96 = 0.072 moles

So moles of ammonium ion = 2 X moles of ammonium carbonate

                                             = 2X 0.072 = 0.144 moles