Atomic mass and moles question here. I have the molar mass of aluminum as 27.0 g/mol, its density at 2.70g/cm^3, the mass of 2.00 cm^3 of aluminum as 5.40 g, and I'm trying to find the number of atoms in that 2.00 cm ^3. I thought it would be 1.20 x10^24, but apparently that's wrong. (My class uses WebAssign, but I did use E notation there.) Does anyone know the correct answer to this or if it's just a technical issue?

Question

joannablackwelder · Answer

I am getting very close to the same, but off by a factor of 10. How many moles did you get?

sapphiremoon · Answer

I have 0.2 moles.

joannablackwelder · Answer

Great! Then how did you convert to atoms from moles?

sapphiremoon · Answer

I multiplied by 6.02 x10^23.

joannablackwelder · Answer

Cool. Try that again. I think you just mistyped it in your calc.

sapphiremoon · Answer

Hmm. Now it's correct, but I did that calculation four times... Thank you so much, though!

joannablackwelder · Answer

No worries. It was E23 not E24 :-)