An unknown mixture containing KClO3 was added to an ignition tube weighting 41.960g, The tube and mixture was then found to weight 43.772g. After the first heating, the tube and its contents weighed 43.621g.

Question

After the second and third heatings, it weighed 43.332g.

1)What mass of oxigen was liberated from the unknown mixture?
2)what mass of KClO3 was contained in the original mixture?
3)what was the percentage of KClO3 in the original mixture?

Answer 1

Note: weigh is spelled without the final t.

43.772 g = mass KClO3 mixture + tube
-41. 960 = mass tube
--------------
?? = mass KClO3 initially.

43.772 = mass KClO3 mixtur + tube
-43.332 = mass after final heating
---------------
?? = loss in mass = mass oxygen

%oxygen = (mass O2/mass KClO3)*100 =

Answer 2

is the lost in mass O? or H2O? sorry.