How many atoms of aluminum are in 2.75 mol of aluminum?

To determine this simply take the number of moles of Al and multiply it by Avogadro’s number which is 6.02 x 10^23 atoms.

This will tell you the number of atoms in that many moles

Atomicity occurs to prevent updates of the database occurring only partially, which can cause greater problems than rejecting the whole series outright.some are monatomic, diatomic, triatomic etc because it shows the number of atoms. for example, monatomic means it contains only one atom.