Weight in grams of a sample of aluminum nitrate, which contains 3.612 x 10 to the 23rd degree of nitrogen atoms ..

The formula of aluminum nitrate is Al (NO3) 3; therefore, there are three moles of nitrogen atoms in each mole of aluminum nitrate. the number of aluminum nitrate molecules is
N = Na * n
N = 3.612 × 10 ^ 23/3 = 1.204 × 10 ^ 23 molecules. Avogadro’s N 6.022 × 10 ^ 23, therefore in our case 1.204 / 6.022 = 0.2 mol of substance. The molar mass of aluminum nitrate is 212.996 g / mol, respectively, the mass of the sample is m = M × n
M = 0.2 + 212.996 = 42.6g