The number of formula units would be 2.5 x [tex]10^2^3[/tex]
This is mathematically given as: mole x Avogadro number
Molar mass of the aluminum sulfide (Al2S3) sample = 26.98 x 2 + 32.06 x 3
= 53.96 + 96.18 = 150.14 g/mole
Mole of 62.2 g aluminum sulfide = 62.2/150.14 = 0.4143 moles
Formular unit = 0.4143 x 6.023 x [tex]10^2^3[/tex] = 2.5 x [tex]10^2^3[/tex]
More on formula units can be found here: https://brainly.com/question/21494857
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