A mole of the element silicon is generally considered to have Avogadro's Number of atoms, since there is no particular small number of silicon atoms that is known to have distinct and persisting chemical bonds different from those of any other part of a sample of silicon. The number shown in the question is about 10 times Avogadro's Number and therefore contains ten moles.
2.80x10^24 atoms x 1 mol/6.02x10^23 atoms = 4.65 moles
2.26*1024
1.20x10^24 atoms x 1 mole/6.02x10^23 atoms = 1.99 moles
(2.16x10^24 atoms) x ( 1 mole/ 6.022x10^23 atoms) = 0.3586848223x10^1 which your answer should be 3.59 moles
2.1 X 1024 atoms (1 mole/6.022 X 1023) = 3.5 moles ========
2,80 1024 atoms of silicon equals 0,465 moles.
3.10 moles SiO2 (1 mole Si/1 mole SiO2)(6.022 X 1023/1 mole Si) = 1.87 X 1024 atoms of silicon =====================
How many moles are there in 9.0333x1024 atoms of helium
2,50 moles of silicon contain 15,055352142.10e23 atoms.
1,67.1024 argon atoms is equal to 2,773 moles.
4.66715966 × 1024
The answer is 15,2 moles.
56 moles × (6.02 × 1023) = 3.37 × 1024 atoms
Multiply by avagadro's number (6.022x1023) giving 3.203704x1023 atoms
2.26*1024
2.80x10^24 atoms x 1 mol/6.02x10^23 atoms = 4.65 moles
2.26*1024