Question

the number of molecules in 6.843*10^-2 kg of Al(NO3)3 is:
and this is what i have done so far... 1st i converted the kg to g which is 6.843*10^-5. then i figured out the moles:6.843*10^-5/213.01 i got 3.21*10^-7. i then multiplied this number by avogadro's number(6.022*10^23) my final answer was 1.933*10^17. but it is not one of my answer choices. can anyone tell me where i went wrong? thanks.

Answer 1

You didn't convert kg to g properly. The conversion factor is 1000 g = 1 kg. Apparently you 1 g = 1000 kg.

Answer 2

I didn't type all my answer. Apparently you used 1 g = 1000 kg.
6.843 x 10^-2 x (1000 g/1 kg) = 6.843 x 10^1 = 68.43 g.