Sub-topic 1
2025 · National Semifinal
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Combining equilibrium constants of sequential/multiplied equilibrium steps
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Sub-topic 2
2024 · National Semifinal
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Mass of a sparingly soluble hydroxide dissolved to form a given volume of saturated solution (ksp)
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Sub-topic 3
2024 · National Semifinal
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Equilibrium constant with units for a gaseous reduction reaction (no + h2 to n2 + h2o)
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Sub-topic 4
2025 · National Semifinal
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Mass of a sparingly soluble oxalate (ksp) that dissolves in a given volume of water
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Sub-topic 5
2026 · National Quarterfinal
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Ionic product of a hydroxide in a mixture formed by mixing two solutions
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Sub-topic 6
2026 · National Quarterfinal
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Acid dissociation constant ka from the percentage ionization of a weak monoprotic acid
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Sub-topic 7
2026 · National Quarterfinal
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Molar solubility of a hydroxide in a solution buffered at a fixed ph
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Sub-topic 8
2026 · National Quarterfinal
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Solubility product of a hydroxide from the ph of its saturated solution
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Sub-topic 9
2026 · National Final
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Solubility product of a hydroxide from the ph of its saturated solution
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Sub-topic 10
2026 · National Quarterfinal
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Equilibrium constant for dissociation of dinitrogen tetroxide from percentage dissociation
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Sub-topic 11
2026 · National One-Eighth
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Ionic product of a sparingly soluble hydroxide after mixing solutions
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Sub-topic 12
2021 · National Preliminary
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Solubility product from dissolved ion concentration
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Sub-topic 13
2021 · National Preliminary
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Solubility product from an evaporated residue mass
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Sub-topic 14
2021 · National One-Eighth
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Constructing a balanced equation from an equilibrium expression
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Sub-topic 15
2024 · National One-Eighth
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Equilibrium constant kc with correct units from equilibrium concentrations
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Sub-topic 16
2025 · National Preliminary
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Equilibrium constant kc with correct units from equilibrium concentrations
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Sub-topic 17
2022 · National Final
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Equilibrium concentration from kc for the decomposition of hydrogen iodide
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Sub-topic 18
2017 · National Quarterfinal
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Identifying the hydrolysing species, its equation, and its pka or pkb from the ph of a 0.10 mol/dm3 salt solution
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Sub-topic 19
2023 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 20
2026 · National One-Eighth
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 21
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 22
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 23
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 24
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 25
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 26
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 27
2026 · National Preliminary
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Solubility product: concentration from ksp, common-ion suppressed solubility, and ionic product after mixing
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Sub-topic 28
2023 · National Preliminary
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Effect of pressure on chemical equilibrium position (true/false)
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Sub-topic 29
2026 · National Preliminary
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Effect of pressure on chemical equilibrium position (true/false)
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Sub-topic 30
2026 · National Preliminary
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Solubility and polarity: like-dissolves-like, ionic compound solubility, and solvent amount (true/false)
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Sub-topic 31
2023 · National Preliminary
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Inferring reaction composition and phase from an equilibrium expression (true/false)
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Sub-topic 32
2024 · National Preliminary
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Predicting the solubility of an ionic product from solubility rules
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Sub-topic 33
2003 · National Semifinal
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Gas solubility in water decreases with increasing temperature
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Sub-topic 34
2013 · National Preliminary
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Freezing-point depression of ice by impurities
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Sub-topic 35
2013 · National Preliminary
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Solubility from ksp for a salt of formula ab2
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Sub-topic 36
2013 · National Preliminary
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Solubility from ksp for a salt of formula ab (1:1 ratio)
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Sub-topic 37
2013 · National Preliminary
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Solubility from ksp for a salt of formula ab2
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Sub-topic 38
2013 · National Preliminary
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Negative reaction enthalpy favours spontaneity (true/false)
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Sub-topic 39
2013 · National Preliminary
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Catalysts in the haber process do not alter equilibrium ammonia yield (true/false)
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Sub-topic 40
2013 · National Quarterfinal
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Statement of hess's law
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Sub-topic 41
2013 · National Quarterfinal
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Statement of graham's law of diffusion
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Sub-topic 42
2013 · National Quarterfinal
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Statement of avogadro's law
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Sub-topic 43
2013 · National Quarterfinal
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Gas laws combining into the ideal gas equation
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Sub-topic 44
2013 · National Quarterfinal
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Charles' law explained via the kinetic theory of gases
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Sub-topic 45
2013 · National Quarterfinal
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Boyle's law explained via the kinetic theory of gases
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Sub-topic 46
2013 · National Quarterfinal
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Partial pressure is proportional to mole fraction, not molar mass (dalton's law) (true/false)
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Sub-topic 47
2013 · National Quarterfinal
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Graham's law: diffusion rate versus density/molar mass (true/false)
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Sub-topic 48
2013 · National Semifinal
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Salt lowers ice's melting/freezing point (freezing-point depression on roads)
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Sub-topic 49
2018 · National Preliminary
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Avogadro's law: equal moles, not equal mass, occupy equal gas volume (true/false)
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Sub-topic 50
2021 · National Semifinal
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Equilibrium concentrations of butane and isobutane from mass balance in an isomerization
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Sub-topic 51
2022 · National Preliminary
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True or false: changing pressure changes the equilibrium constant
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Sub-topic 52
2022 · National Preliminary
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True or false: changing product concentration changes the equilibrium constant
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Sub-topic 53
2022 · National Preliminary
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True or false: changing temperature changes the equilibrium constant
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Sub-topic 54
2022 · National Preliminary
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Maximum chloride concentration to precipitate lead(ii) chloride, from ksp
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Sub-topic 55
2022 · National Preliminary
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Solubility product of calcium oxalate from its solubility
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Sub-topic 56
2022 · National Preliminary
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Solubility product of iron(ii) hydroxide from its fe2+ concentration
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Sub-topic 57
2023 · National Preliminary
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True or false: a decomposition reaction always breaks a single reactant into two or more products
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Sub-topic 58
2023 · National Preliminary
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True or false: a decomposition reaction always requires an external source of energy
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Sub-topic 59
2023 · National Preliminary
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True or false: a decomposition reaction may involve both chemical and physical changes
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Sub-topic 60
2023 · National Preliminary
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True or false: for a gaseous reaction, changing pressure always changes the equilibrium direction
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Sub-topic 61
2023 · National Preliminary
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True or false: increasing pressure shifts equilibrium toward the side with more moles
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Sub-topic 62
2023 · National One-Eighth
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Ksp expression for lithium carbonate
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Sub-topic 63
2023 · National One-Eighth
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Ksp expression for magnesium phosphate
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Sub-topic 64
2023 · National One-Eighth
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Ksp expression for aluminum sulfate
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Sub-topic 65
2023 · National Preliminary
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Equilibrium constant kc for a+b⇌2c from given equilibrium concentrations
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