Question

Chemistry help? 10 points!?

An atom of gold has a mass of 3.271 x 10^-22g. How many atoms of gold are in 5.00 g of gold?

can someone tell me how to do this problem?

Answer

5.00/3.271x10^-22 = 1.5x10^22 atoms of gold

Dec 8 at 1:4

I'm not going to use the mass of an individual atom of gold; rather I'm going to convert the mass of gold to moles, then multiply by Avogadro's number to get the number of atoms. So,

5.00 g Au / 196.97 g/mol = 0.025 mol * 6.02e23 atoms/mol = 1.53e22 atoms Au

Dec 8 at 4:50