[rox1co]

A mixture containing KClO3, K2CO3, KHCO3, and KCl was heated, producing CO2, O2, and H2O gases according to the following reactions:
2KClO3(s) → 2KCl(s) + 3O2(g)
2KHCO3(s) → K2O(s) + H2O(g) + 2CO2(g)
K2CO3(s) → K2O(s) + CO2(g)
The KCl does not react under the conditions of the reaction. If 100.0 g of the mixture produces 1.80 g of H2O, 13.20 g of CO2, and 4.00 g of O2, what was the composition of the original mixture? (Assume complete decomposition of the mixture.)

i've successfully gotten the amount of KClO3 & KHCO3; however, K2CO3 is giving me trouble (i'm thinking that maybe K2O is the limiting reagent, but how do i get that?)

*point the arrow the other way to make it look like a regular Limiting Reactant problem.

answers: KClO3 = 10.2g, KHCO3 = 20.0g, K2CO3 = 13.8g (eh? idk why i'm not getting it), KCl does not react so it's just 100g - (KClO + KHCO3 + K2CO3) = 56.0g

thanks for any help

[DevaDevil]

don't worry about the K₂O

The trick lies in the CO₂, which is produced by 2 reactions.

[rox1co]

don't worry about the K₂O

The trick lies in the CO₂, which is produced by 2 reactions.

i don't understand?  could you please elaborate or give me a hint to where i can read about it, thanks!!!

"assume complete decomposition of the mixture" ... hmmm

edit:  OMG!!!  water was the limiting reagent for the formation of K2CO3 ... holy crap, thanks! (13.20 g of CO2 was given to throw me off)

is it safe to assume that the decomposition of potassium bicarbonate produced potassium carbonate but that was unstable so it decomposed to potassium oxide and carbon dioxide?