Question

1.A sample of sodium chloride (NaCl) has a mass of 28.36g. Calculate the number of moles of NaCl in the sample. Show your work.
2.Calculate the number of moles of each element (number of moles of Na and number of moles of Cl) in NaCl in the sample. ( use your answer from part 1) show your work.
3.Calculate the number of atoms of each element (number of atoms of Na and number of atoms of Cl) in NaCl in the sample. (Use you answers from part 2) show your work

Answer 1

to get moles. divide mass by molar mass.
Molar mass of Na is 23 and for Cl is 35.5. the total molar mass is 
23+35.5 = 58.5mol/g
Use the mass and divide by this number
28.36g divide by 58.5mol/g and you will get 0.485 mole.

Since the molecule has 1 Na to 1 Cl, and that the number of moles for NaCL is 0.485. All of them would be 0.485moles
Na = 0.485 x 1 = 0.485moles
Cl = 0.485 x 1 = 0.485moles

to get number of atoms. Multiply your mole by Avogadro number which is 6.022E23
Na = 0.485 x 6.022E23 = 2.92x10^23
Cl =  0.485 x 6.022E23 = 2.92x10^23