Answer: The atoms of lead are more closer together.
Step-by-step explanation:
Lead is more dense than aluminium as the atoms are more closely attached as compared. The arrangement of atoms in the aluminium is far as compared to the to lead.
The atoms of lead have very less space in between them and the atoms of aluminium are loosely packed so has less density than lead.
Lead is heavy as compared to that of aluminum and is denser as well. The density of lead is 11.4 g/cc and aluminum is 2.7 g/cc.