Sub-topic 1
2026 · National Preliminary
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Molecular formula of the nth member of a homologous series
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Sub-topic 2
2026 · National Preliminary
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Systematic name of an organic compound from its molecular formula (degree of unsaturation)
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Sub-topic 3
2025 · National Preliminary
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Total number of atoms in an empirical formula unit derived from a molecular formula
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Sub-topic 4
2026 · National Semifinal
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Number of hydrogen atoms from carbon count and degrees of unsaturation
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Sub-topic 5
2026 · National Quarterfinal
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Degree of unsaturation of an aromatic nitro compound
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Sub-topic 6
2024 · Regional Championship
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Empirical formula atom count of a homologous series member
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Sub-topic 7
2026 · National One-Eighth
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Empirical formula atom count of a homologous series member
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Sub-topic 8
2026 · National One-Eighth
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Molecular formula from percentage composition and molar mass
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Sub-topic 9
2026 · National Preliminary
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Molecular formula from percentage composition and molar mass
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Sub-topic 10
2023 · National One-Eighth
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Riddle: hexanal, a straight-chain aldehyde
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Sub-topic 11
2023 · National One-Eighth
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Mass of an element within a given mass of a hydrocarbon
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Sub-topic 12
2021 · National Preliminary
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Percentage composition, empirical and molecular formula
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Sub-topic 13
2021 · National Preliminary
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Empirical and molecular formula from mass/composition data
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Sub-topic 14
2023 · National Preliminary
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Systematic name of a carbonyl compound from its molecular formula
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Sub-topic 15
2025 · Regional Championship
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Systematic name of a carbonyl compound from its molecular formula
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Sub-topic 16
2025 · Regional Championship
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Systematic name of a carbonyl compound from its molecular formula
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Sub-topic 17
2026 · National Preliminary
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Systematic name of a carbonyl compound from its molecular formula
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Sub-topic 18
2026 · National Preliminary
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Systematic name of a carbonyl compound from its molecular formula
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Sub-topic 19
2026 · National Preliminary
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Riddle: chloroform
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Sub-topic 20
2024 · National One-Eighth
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Effect of increasing molar mass on physical properties of alkanes
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Sub-topic 21
2024 · National One-Eighth
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Systematic naming of organic compounds from structure
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Sub-topic 22
2024 · National One-Eighth
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Degree of unsaturation of an aromatic hydrocarbon
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Sub-topic 23
2026 · National Preliminary
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Maximum number of hydrogen atoms in a straight-chain compound with given halogens and double bonds
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Sub-topic 24
2026 · National Preliminary
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Riddle: dichloromethane, a chlorinated organic solvent
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Sub-topic 25
2026 · National Preliminary
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Riddle: dichloromethane, a chlorinated organic solvent
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Sub-topic 26
2026 · National Preliminary
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Riddle: dichloromethane, a chlorinated organic solvent
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Sub-topic 27
2024 · National Preliminary
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Cyclopropane: the simplest cycloalkane and its angular strain (true/false)
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Sub-topic 28
2023 · National Preliminary
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Identifying a possible functional group family from a molecular formula alone
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Sub-topic 29
2023 · National Preliminary
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Molar mass of a branched alkane from its systematic name
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Sub-topic 30
2003 · National Semifinal
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The carbonyl functional group of alkanones (ketones)
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Sub-topic 31
2013 · National Preliminary
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Systematic naming of a straight-chain alkane from carbon count
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Sub-topic 32
2013 · National Preliminary
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Systematic name of a symmetrical straight-chain alkanone
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Sub-topic 33
2013 · National Preliminary
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Reagent converting ethene to a 1,2-dihaloalkane
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Sub-topic 34
2013 · National Preliminary
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Reagent converting ethene to ethylene glycol via cold dilute kmno4
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Sub-topic 35
2013 · National Preliminary
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Reagent converting ethene to chloroethane
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Sub-topic 36
2013 · National Preliminary
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Systematic names of cyclobutane derivatives with formula c6h12
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Sub-topic 37
2013 · National Preliminary
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Naming all possible hexenes with formula c6h12
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Sub-topic 38
2013 · National Semifinal
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Strong, low-reactivity c-h bonds underlying hydrocarbon stability
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Sub-topic 39
2013 · National Semifinal
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Functional groups determining physical/chemical properties of organic molecules
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Sub-topic 40
2022 · National Preliminary
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Possible structures for the organic compound c4h6 (2 degrees of unsaturation)
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Sub-topic 41
2023 · National Preliminary
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Riddle: formaldehyde, the simplest aldehyde used to preserve dead organisms
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Sub-topic 42
2023 · National Preliminary
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Empirical formula of 3-ethyl-4-methyl-1-pentyne, c8h14 reducing to c4h7
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Sub-topic 43
2023 · National Preliminary
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Reduction converts an alkyne to an alkene
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Sub-topic 44
2023 · National Preliminary
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True or false: rcho represents an aldehyde
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Sub-topic 45
2023 · Regional Championship
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Riddle: butane, a four-carbon alkane component of lpg
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