9.25 moles of copper (II) Nitrate contains how many atoms?
You need the chemical formula for copper(II) nitrate, Cu(NO3)2 Determine how many moles of Cu(NO3)2 you have in 10.2 g moles of N atoms = 2 * moles of Cu(NO3)2 based on the chemical formula atoms of N = moles of N * Avogadro's number 6.5 * 10^22.