Question

My original sample of mixed salt had a mass of 8.9 grams. After heating the mixture in the crucible and weighing it multiple times my final mass of salt ended up being 4.9. How many moles of oxygen were driven off?
Lost on how to do this been a while since I have done this.

Answer 1

Assuming the only ingredients could be decomposed to give oxygen (and nothing else) then oxygen driven off must have been 8.9-4.9 = ? Then mol = grams/molar mass.