The mole is used in chemistry A) to count large numbers of very small particles, such as atoms or molecules.
B) to relate the mass and the number of particles of a substance to each other.
C) to relate the mass and the volume of a substance to each other.
D) all of these are true.

Avogadro's number is defined as the number of elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is equal to 6.022×1023 mol-1 and is expressed as the symbol NA. Avogadro's number is a similar concept to that of a dozen or a gross.

So I think it’s either D or C

Answer/// he concludes that the atom particles can be broken due to the paddle wheel being moved by particles coming out of the metal;