Mass Composition Of A Mixture Of KClO3, KHCO3, K2CO3 And KCl
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Mass Composition Of A Mixture Of KClO3, KHCO3, K2CO3 And KCl

A mixture containing KClO3, KHCO3, K2CO3 and KCl was heated. CO2, O2 and H2O gases were produced as follows:

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 g of the mixture produces 1.80 g of H2O, 13.20 g of CO2 and 4.0 g of O2, what was the mass composition of the original mixture if the mixture decomposed completely?

The strings: S7P1A15 (containership-mass).
S7P6A66 (grouping/interaction- chemical)

The math:
Both Pj Problem are of Interest, however, Pj Problem of type grouping/interactio (chemical) is in focus.

Decomposition Of KClO3:
Molar mas of O2 = 16 x 2 = 32 g
So, 4 g of O2 = 4/32 = 0.125 mol of O2
3 mols of O2 is produced from 2 moles of KClO3 decomposition
So, 0.125 mol of oxygen is produced from (2x0.125)/3 = 0.083 mol of KClO3
Molar mass of KClO3 = 39 + 36 + 48 = 123 g
So, mass of 0.083 mol of KClO3 = (0.083 x 123) = 10.25 g.

Decomposition of KHCO3:
Molar mass of H2O = 1x2 + 16 = 18
So, 1.80 g of H2O = 1.80/18 = 0.1 mol of H2O
1 mole of H2O is produced by 2 moles of KHCO3
So, 0.1 mol of H2O is produced from 0.2 mol of KHCO3
Molar mass of KHCO3 = 39 + 1 + 12 + 48 = 100 g
So, mass of 0.2 mol of KHCO3 = 0.2 x 100 = 20 g.

CO2 is also produced:
20 g of KHCO3 = 20/100 = 0.2 mol
2 moles of KHCO3 produced 2 moles of CO2
So, 0.2 mol KHCO3 produced 0.2 mol of CO2
Molar mass of CO2 = 12 +32 = 44
So, mass of CO2 produced = (0.2 x 44) = 8.8 g

Decomposition of K2CO3:
13.20 - 8.8 = 4.4 g = mass of CO2 produced
Molar mass of CO2 = 12 + 32 = 44
So, mol of CO2 produced = 4.4/44 = 0.1 mol
1 mole of K2CO3 produced 1 mole of CO2
So, 0.1 mol of K2CO3 produced 0.1 mol of CO2
Molar mass of K2CO3 = 2x39 + 12 + 3x16 = 78 + 12 + 48 = 138
So, mass of 0.1 mol of K2CO3 = (0.1x138) = 13.8 g

mass of KCl = 100 -(10.25 + 20 + 13.8) = 100 - 44 = 56 g

Mass composition of mixture is as follows:
10.25 g KClCO3, 20 g KHCO3
13.8 g K2CO3, 56 g KCl.

Math

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