Step 1
Avogadro's Number states that:
1 mole of Al(OH)3 = 6.02x10^23 formula units (molecules in this case)
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Step 2
Information provided:
1.25 moles of Al(OH)3
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Step 3
Procedure:
1 mole Al(OH)3 --------- 6.02x10^23 molecules
1.25 moles Al(OH)3 --------- X
X = 1.25 moles Al(OH)3 x 6.02x10^23 molecules/1 mole Al(OH)3
X = 7.53x10^23 molecules of Al(OH)3
Answer: 7.53x10^23 molecules of Al(OH)3
