Question

Find the total number of atoms in a sample of cocaine hydrochloride, c17h22clno4, of mass 22.5 mg .

Answer 1

Total MW: C: 17(12.0) = 204.0 H: 22(1.01) = 22.22 Cl: 1(35.453)= 35.453 N: 1(14.0) = 14.0 O: 4(16.0) = 64.0 Total: 339.7 g/mole Total number of atoms: 17+22+1+1+4 = 45 (22.5 x 10^-3 g)(1 mole/339.7 g)(6.022 x 10^23 molecules/mole)(45 total atoms/ molecules) =1.79 x 10^21 total atoms