A lead atom has a mass of 3.4⋅10^-22 g. How many lead atoms are in a cube of lead that has a volume of 2.07 cm^3 if the density of lead is 11.3 g/cm^3?

Answer 1

volume = 2.07 cc
density = 11.3
mass = volume x density = 2.07 x 11.3 = about 23g but you should be more exact than that.
Then 3.4E-22 x # Pb atoms = about 23 g
Solve for # Pb atoms.

Answer 2

so, is it equal 6.9*10^22 ?