Question

To the nearest whole number, how many moles are in a 120-gram sample of calcium metal? How many atoms is this?

Answer 1

(sample g/1) X (1 mole/40.078(MW of Ca)) = moles of sample

(moles of sample)(6.022 x 10^23( no of atoms)/ 1 mole) = # of atoms in a 120 g sample of calcium


Avogadro's number=6.022x 10^23 atoms in 1 mole