how to calculate the mass and volume of oxygen released when 29,4 g potassium chlorate decomposes to form potassium chloride and oxygen?

2 answers

how many moles of KClO3 in 29,4 grams?
Look at the balanced equation to see how many moles of O2 are produced by each mole of KClO3.
Convert that to grams of O2
For volume, recall that 1 mole occupies 22,4 L at STP.
The equation is
2KClO3 ==> 2KCl + 3O2