Question

How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.11 g/mol.. . 4 KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)

Answer 1

The balanced reaction is:

4KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)

We are given the amount of potassium nitrate for the reaction to use. This will be the starting point for the calculations.

58.6 g KNO3 (1 mol KNO3 / 101.11 g KNO3 ) ( 5 mol O2 / 4 mol KNO3 ) = 0.7245 mol O2

Therefore, the amount of O2 produced from the reaction was 0.7245 moles.