Answer:
Option C. 0.7x10^2 moles
Explanation:
1mole of a substance contains 6.02x10^23 atoms as discovered from Avogadro's hypothesis.
If 1 mole of Ne contains 6.02x10^23 atoms,
Therefore, Xmol of Ne will contain 4.2154x10^25 atoms i.e
Xmol of Ne = (4.2154x10^25)/6.02x10^23 = 70moles = 0.7x10^2 moles