Sub-topic 1
2025 · National Preliminary
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Riddle: filtration, a solid-liquid/gas separation technique
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Sub-topic 2
2012 · National Preliminary
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Problem of the day: separating a colored solid mixture by column chromatography
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Sub-topic 3
2013 · National Quarterfinal
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Riddle: crystallization from saturated solution
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Sub-topic 4
2013 · National Quarterfinal
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Brick-red precipitate with fehling's reagent indicates a reducing sugar
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Sub-topic 5
2013 · National Quarterfinal
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Blue-black colour with iodine indicates starch
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Sub-topic 6
2016 · National One-Eighth
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The beaker as suitable glassware for dissolving a solid in a moderate water volume
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Sub-topic 7
2016 · National One-Eighth
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Differences between a watch glass and an evaporating dish
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