moles in chemistry

Question

after eating a plate full of super-hot wongs, Fustin needed 1.50g of Mylanta (Milk of Magnesia) in a hurry. How many molecules of Mylanta did he need to settle his stomach? The molecular formula of milk of magnesia is Mg(OH)2

Answer 1

Molar mass Mg(OH)₂ = 58.32 g/mole

Convert g to moles and then use Avogadro's number to convert moles to molecules (formula units in this case)

1.50 g Mg(OH)₂ x 1 mole/58.32 g x 6.02x10²³ molecules/mole = 1.55x10²² molecules (formula units)