Sub-topic 1
2025 · National Preliminary
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Sum of coefficients in a balanced hydrocarbon combustion equation
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Sub-topic 2
2025 · National One-Eighth
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Balancing equations: sum of coefficients
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Sub-topic 3
2025 · National One-Eighth
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Balancing equations: sum of coefficients
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Sub-topic 4
2025 · National One-Eighth
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Balancing equations: sum of coefficients
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Sub-topic 5
2026 · National One-Eighth
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Balancing equations: sum of coefficients
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Sub-topic 6
2026 · National One-Eighth
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Balancing a thermal decomposition equation
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Sub-topic 7
2021 · National Preliminary
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Balancing equations: sum of coefficients
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Sub-topic 8
2021 · National One-Eighth
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Balancing equations: sum of coefficients
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Sub-topic 9
2021 · National Preliminary
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Balancing equations: sum of coefficients
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Sub-topic 10
2025 · National Final
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Volume of gas released from a rocket-fuel reaction using balanced equation stoichiometry
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Sub-topic 11
2023 · National Final
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Mass of product formed from a redox equation balanced by oxidation-state electron transfer
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Sub-topic 12
2024 · Regional Championship
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Mass of a reactant needed to produce a given amount of product, from a balanced equation
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Sub-topic 13
2017 · National Semifinal
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Balancing and applying the softening reaction of temporary hardness with slaked lime
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Sub-topic 14
2017 · National Quarterfinal
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Balanced equation for the softening reaction of temporary hardness with slaked lime
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Sub-topic 15
2021 · National Preliminary
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Sum of stoichiometric coefficients in balanced nh4no3 decomposition
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Sub-topic 16
2021 · National Preliminary
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Sum of stoichiometric coefficients in balanced n2+o2+h2o→hno3
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Sub-topic 17
2021 · National Preliminary
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Sum of stoichiometric coefficients in balanced nh3+o2→n2+h2o
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Sub-topic 18
2021 · National Preliminary
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Sum of stoichiometric coefficients in balanced b2br6+hno3→b(no3)3+hbr
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Sub-topic 19
2022 · National Preliminary
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Sum of stoichiometric coefficients in balanced al(oh)3+h2so4→al2(so4)3+h2o
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Sub-topic 20
2022 · National Preliminary
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Sum of stoichiometric coefficients in balanced h2s+ag(nh3)2oh→h2o+nh3+ag2s
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Sub-topic 21
2022 · National Preliminary
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Sum of stoichiometric coefficients in balanced c+hno3→no2+co2+h2o
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Sub-topic 22
2022 · National Preliminary
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Sum of stoichiometric coefficients in balanced 3o2+4ch4→6h2o+2c2h2
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Sub-topic 23
2023 · National Preliminary
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Sum of reactant coefficients in balanced complete combustion of benzene
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Sub-topic 24
2023 · National Preliminary
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Sum of coefficients for combustion of iron pyrite (fes2) to iron(ii) oxide and sulfur dioxide
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