I think you have answered the question but not the correct way. You have solved the simple stoichiometry problem and calculated the mass oxygen based on your knowledge that O2 has a molar mass of 32. The question doesn't ask what mass of O2 is produced.
I think the answer is yes, also, but only if the volume is measure at the same time. I think it is done this way.
Weigh KClO3 before heating.
Weigh KClO3 after heating (and cooling).
Subtract; the difference is the mass of oxygen evolved. [Note:If you know ONLY the mass oxygen at this point, no, you can't calculate the molar mass.]
Collect the O2 produced. Measure the volume of O2 collected. Correct the volume for the vapor pressure of water in the collection bottle (it usually is collected over water by water displacement), for pressure and temperature to STP. Now you have grams O2 evolved and volume O2 produced; you can calculate the mass of 22.4 L of oxygen which will be the molar mass.
[Note:IF you have the mass AND the volume, you CAN measure the molar mass oxygen.] Check my thinking.
Based on the mass of O2 produced can you calculate the gram molecular weight?
Chem lab on oxygen production
10g KClO3 reacts with heat to produce 2KCl(s)+3O2.What is the mass produced?
10g/122.6=0.0816 mole of KClO3
0.00816x3moleO2/2moleKClO3=0.1224 moleO2
0.1224 molex32g O2/1mole O2=3.9168gO2
I believe the answer to can you calc the gmw is yes. I know the gmw of O2 is 32by working from the periodic table and atomic mass. or is 3.9168 the answer? or am I missing a conversion? My concern is that I have this value of 3.9 g of O2 produced.
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