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Anonymous users2024-01-24A. Tap water and liquor, the smell of the two hidden locust is different, there is a special fragrance to gain and lose liquor, and there is no smell of tap water, which can be distinguished by others
B. Sodium carbonate can react with acid to produce bubbles, but refined salt cannot; Vinegar is added separately, sodium carbonate is produced by bubbles, and refined salt is not significantly changed, and the vinegar in the kitchen can be used to complete the identification
C. To determine the pH of vinegar, you need to use pH test paper or pH meter, and the reagent used is not a kitchen product, and the experiment cannot be completed in the "small family experiment".
D. Sodium carbonate can react with acid to produce carbon dioxide gas, using candles, matches, glasses and other supplies, it can be verified that carbon dioxide can extinguish fires, and these supplies can be completed by using kitchen stove manuscript friends
So choose C
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Anonymous users2024-01-23CA can be distinguished by smelling the smell, B adds vinegar and produces sodium carbonate by bubbles, C cannot be completed, D uses sodium carbonate powder and vinegar to produce carbon dioxide to extinguish the lit match, so C is chosen
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