0.206 moles if question is actually correctly worded (unlikely)
0.633 M if question should have asked about molarity (likely).
First, let's calculate how many moles of ammonium chloride (NH4Cl) we have. Start by looking up the atomic weights of involved elements.
Atomic weight nitrogen = 14.0067
Atomic weight hydrogen = 1.00794
Atomic weight chlorine = 35.453
Molar mass NH4Cl = 14.0067 + 4*1.00794 + 35.453 = 53.49146 g/mol
Moles NH4Cl = 11.0 g / 53.49146 g/mol = 0.205640302 moles
Now technically, I already have the answer to this problem in that there is 0.205640302 moles of ammonium chloride in the solution. Doesn't matter if 325 mL were made, or 1000 liters. The total number of moles of ammonium chloride remains the same. But I suspect that this question was improperly worded and that what is actually being looked for is the molarity of the resulting solution. And since molarity is defined as moles per liter, a bit of division is needed. So:
0.205640302 mol / 0.325 L = 0.632739391 mol/L = 0.632739391 M
Rounding results to 3 significant figures gives 0.206 moles and 0.633 M.
