How to calculate the number of moles of cl atoms in 1.81×1024 formula units of magnesium chloride, mgc l 2 .

For ever molecule of MgCl2, there are 2 Cl atoms.

1.81 x 10^24 molecules MgCl2 x 2 = 3.62 x 10^24 atoms Cl

3.62 x 10^24 atoms Cl x 1 mol / 6.022 x 10^23 = 6.01 moles Cl

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