Chem
posted by Ezra .
How many moles of ammonium ions are in 8.794g of ammonium carbonate?
I got .1832 as an answer and I was told that I was very close and I just may have done some kind sigfig or calculation error but I have no idea what it is since I did this problem so many times only to get the same answer.

When you post a question like this it keeps us in the dark. In addition to the problem you should have posted you work. That way we could find the error.
What are you using for the molar mass of (NH4)2CO3? I have it as 96.086.
8.794/96.086 = 0.09152
mols NH4^+ is twice that so
0.09152*2 = 0.18304 which I would round to 0.1830. 
Yeah it was that last digit that threw me off. Thanks for the help. I rounded early so the calculation came out different.