Answer :
Moles of Helium = 2
Further explanation
Given
12.04 x 10²³ atoms of helium
Required
moles
Solution
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
moles Helium :
n = N : No
n = 12.04 x 10²³ : 6.02 x 10²³
n = 2