Number of moles = 78.41
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
4.72 x 10²⁵ atoms of a substance, then moles :
[tex]\tt n=\dfrac{N}{No}\\\\n=\dfrac{4.72\times 10^{25}}{6.02\times 10^{23}}\\\\n=78.41[/tex]