Sub-topic 1
2026 · National Semifinal
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Rate constant with units from a rate law r = k[a]^2[b]^3
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Sub-topic 2
2026 · National Quarterfinal
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Activity of a radioactive isotope remaining after a given number of half-lives
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Sub-topic 3
2026 · National One-Eighth
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Overall reaction order from individual rate-concentration factors
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Sub-topic 4
2021 · National Preliminary
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How reaction rate is (and is not) determined (true/false)
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Sub-topic 5
2026 · National One-Eighth
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Riddle: adsorption, a surface phenomenon used by activated charcoal and silica gel
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Sub-topic 6
2003 · National Semifinal
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Gas diffusion rate increases with temperature
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Sub-topic 7
2013 · National Preliminary
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The rule-of-thumb temperature rise that doubles reaction rate (true/false)
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Sub-topic 8
2013 · National Preliminary
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Catalysts are chemically unchanged at the end of a reaction (true/false)
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Sub-topic 9
2013 · National Preliminary
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Homogeneous catalysts are not inhibitors (true/false)
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Sub-topic 10
2013 · National Preliminary
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Definition of the rate constant of a reaction
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Sub-topic 11
2013 · National Preliminary
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Meaning of a second-order reaction
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Sub-topic 12
2013 · National Preliminary
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Determining reaction order from how rate scales when concentration doubles (order 3)
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Sub-topic 13
2013 · National Preliminary
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Determining reaction order from how rate scales when concentration doubles (order 2)
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Sub-topic 14
2013 · National Preliminary
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Determining reaction order from an unchanged rate despite concentration change (zero order)
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Sub-topic 15
2016 · National One-Eighth
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Rate constant of a first-order reaction from its half-life
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Sub-topic 16
2019 · National Preliminary
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Half-life of a first-order reaction from its rate and initial concentration
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Sub-topic 17
2019 · National Preliminary
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Characteristics of explosive chemical reactions
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Sub-topic 18
2019 · National Preliminary
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Rate constant of a second-order reaction from its rate and concentration
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Sub-topic 19
2019 · National Preliminary
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Rate constant of a first-order reaction from its half-life
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Sub-topic 20
2021 · National Quarterfinal
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True or false: the rate constant can numerically equal the rate under certain conditions
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Sub-topic 21
2021 · National Quarterfinal
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True or false: second order reactions always involve two different reactant molecules
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Sub-topic 22
2021 · National Quarterfinal
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True or false: second order reactions must involve at least two reaction steps
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Sub-topic 23
2023 · National Preliminary
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True or false: enzymes may be denatured during catalytic reactions
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Sub-topic 24
2023 · National Preliminary
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True or false: enzymes may catalyze both forward and backward reactions
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Sub-topic 25
2023 · National Preliminary
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True or false: enzymes help produce more product during chemical reactions
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Sub-topic 26
2023 · National Preliminary
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True or false: for a+2b⇌c+3d, the rate law is [a][b]²
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Sub-topic 27
2023 · National Preliminary
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True or false: for a+2b⇌c+3d, the rate law is k[a][b]²
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Sub-topic 28
2023 · National Preliminary
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True or false: for a+2b⇌c+3d, the reaction order is three with respect to both reactants
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Sub-topic 29
2023 · National Preliminary
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True or false: increasing temperature always increases reaction rate
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