Chemistry
posted by michelle .
how can i find out how many moles of oxygen are in 9.85g of (NH4)2CO3 ?
i want to know what steps to take and in what order.. please help

1. Find moles (NH4)2CO3 = g/molar mass
2. There are 3 oxygen atoms in 1 molecule (NH4)2CO3; therefore, multiply #1 by 3.
3. Note: That will be moles of oxygen atoms; moles of oxygen molecules (O2 and not O) will be 1/2 of #2.