1. Avogadro's Number:

* Avogadro's number tells us the number of particles (atoms, molecules, etc.) in one mole of a substance. It's approximately 6.022 x 10^23 particles/mol.

2. Calculation:

* Divide the number of molecules by Avogadro's number:

(4.651024 molecules) / (6.022 x 10^23 molecules/mol) = 7.72 x 10^-20 moles

Therefore, there are approximately 7.72 x 10^-20 moles in 4.651024 molecules of NO2.