How many lead atoms are in a cube of lead that has a volume of 2.12 cm3 if the density of lead is 11.3 g/cm3?

The number of lead atoms that are in a cube of lead that has a volume of 2.12 cm³ if the density of lead is 11.3 g/cm³ is 6.959 x10^22 atoms

calculation

step 1:find the mass of lead = density x volume

= 2.12 cm³ x 11.3 g/cm³=23.96 grams

step 2: find the number of moles of lead

moles = mass/molar mass

23.96 g/207.2 g/mol = 0.1156 moles

step 3: use the Avogadro's law constant to find the number of atoms

that is 1 mole = 6.02 x10^23 atoms

0.1156mole = ? atoms

by cross multiplication

(0.1156 moles x 6.02 x10^23) : 1 mole=6.959 x10 ^22 atoms