The number of atoms of Hg in 4.5 mole sample has been given as [tex]\rm 2.7099\;\times\;10^2^4[/tex]. Thus, option A is correct.
The number of atoms in a mole of sample has been given by Avogadro number. Avogadro number has been a constant and has been given the value of [tex]\rm 6.023\;\times\;10^2^3[/tex].
The number of atoms in a mole of sample has been given as:
[tex]\rm 1\;mole=\;6.022\;\times\;10^2^3[/tex]
The given sample has been consisted of 4.5 moles of Hg. Thus, the number of atoms in the sample has been given by:
[tex]\rm 1\;mole\;Hg=\;6.022\;\times\;10^2^3\;atoms\\4.5\;mol\;Hg=4.5\;\times\;6.022\;\times\;10^2^3\;atoms\\4.5\;mol\;Hg=27.099\;\times\;10^2^3\;atoms[/tex]
The scientific notation has been the short hand used for writing the numbers. The short hand for atoms in 4.5 moles of Hg has been [tex]\rm 2.7099\;\times\;10^2^4[/tex].
Thus, the number of atoms of Hg in 4.5 mole sample has been given as [tex]\rm 2.7099\;\times\;10^2^4[/tex]. Thus, option A is correct.
For more information about the number of atoms, refer to the link:
https://brainly.com/question/20672430
