2KClO3 → 2KCl + 3O2

How many moles of oxygen are produced by the decomposition of 6.0 moles of potassium chlorate, KClO3?

Question 7 options:

2.0 moles

3.0 moles

6.0 moles

9.0 moles

From the balanced equation 3 moles of oxygen are produced from 2 molecules of potassium chlorate.

So the number of moles of oxygen from 1 mole of chlorate = 3/2 = 1.5.

By proportion the number of moles produced from 6 moles of the chlorate =

= 6 * 1.5 = 9 moles (answer).