Question

An antacid contains 200mg of aluminum hydroxide and 200 mg of magnesium hydroxide per capsule.

How many moles of aluminum hydroxide does each capsule contain?

What is the mass in milligrams of 0.0734 mole of magnesium hydroxide?

Answer 1

mols Al(OH)3 = grams Al(OH)3/molar mass Al(OH)3 = ?

To do part b just rearrange the equation above to grams = mols x molar mass and substitute the data for Mg(OH)2. Remember to convert grams to mg at the end.