How many formula units make up 11.8 g of Magnesium Chloride (MgCl2)

Avogadro's number represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles.

11.8 g (1 mol / 95.21 g) (6.022 x 10^23 formula units / mol) = 7.46 x10^22 formula units

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