Since the product of zero with any other number(s) is zero, there are no moles in the question as written. If 5.5 X 1023 was intended to be written instead of "5.5x0x1o23", the answer is (5.5 X 1023 )/(Avogadro's number) = 0.83 moles, to the justified number of significant digits.
1,638 moles contain 9,864266723766.10e23 atoms.
20 moles
This is equivalent to 1,4 moles.
There are twice as many oxygen atoms as carbon atoms in carbon dioxide, so 100.0 moles of carbon dioxide would contain 200.0 moles of oxygen atoms.
1,0.10e9 atoms is equivalent to 0,166.10e-14 moles.
8.93 1021 atoms equal 0,0148 moles.
Seventeen moles of hydrogen correspond to 204,75.10e23 atoms.
2,50 moles of silicon contain 15,055352142.10e23 atoms.
10,0 moles of bromine atoms contain 60,22140857.1023 atoms.Attention: valid for bromine atoms !.
The number of chlorine atoms in 2,00 moles of CCl4 is 48,113.10e23.
6,1x10-3 moles of carbon 36,7350592277.1020 atoms.
2,80 1024 atoms of silicon equals 0,465 moles.