Question

How many mole of KClO3 are needed to make 320g O2

Answer 1

2KClO3 ==> 2KCl + 3O2

How many mols O2 in 320 g? That's mol = grams/molar mass = ?

Then 2 mols KClO3 = 3 mols O2; therefore,
.....x mols KClO3 = ? mols O2.