Answer:
[tex]1.2646\times10^{25}\ atoms[/tex]
Explanation:
-The chemical formula for Molybdenum (V) Dichromate is [tex]Mo(Cr_2O_7)_3[/tex]
-There are 21 moles of oxygen per one mole of Molybdenum (V) Dichromate
-We apply Avogadro's constant to find the number of atoms of oxygen:
[tex]Avogadro's \ Constant=6.022\times 10^{23} \ mol_1\\\\No\ of \ Atoms=Moles\times Avogadro's \ Constant\\\\=21\times 6.022\times 10^{23} \\\\=1.2646\times10^{25}\ atoms[/tex]
Hence, there are [tex]1.2646\times10^{25} \ atoms[/tex]
