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Anonymous users2024-02-15This should be analyzed from a chemical point of view, alcohol and water can be mixed in any proportion, and after mixing, it is called a solution, and the solution is a stable liquid, which does not separate the solvent from the solute by centrifugation, standing, etc., like emulsions or suspensions. In addition, some solutions such as brine can be separated from salt and water by distillation cooling, and the water is evaporated by heat, leaving behind a solid that is salt, but this method cannot be used to separate mixtures of alcohol and water, because alcohol and water will volatilize when heated. I hope the landlord is satisfied.
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Anonymous users2024-02-14There was a problem where a mixture of alcohol and water was frozen in a refrigerator at -5°C, but in the end it was impossible to separate the two. Among them, we know that the freezing point of water is 0°, and the freezing point of alcohol is -117°, so why is the water not frozen and separated from the alcohol in the end? Here's what I think:
If water is to freeze, in addition to bringing its temperature to 0°, it is also necessary to continue to exothermic (this is an important condition), that is, if it can get heat from the outside world, it will never freeze.
Alcohol just provides such a condition, alcohol in the -5 ° refrigerator is far from reaching the coagulation state, it will only continue to release heat, but can never reach -117 °, that is, can not reach the freezing point, so alcohol and water are always liquid, can not be separated.
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Anonymous users2024-02-13If water is to be frozen, in addition to bringing its temperature to 0°, it is also necessary to make it continue to release heat (this is an important condition), that is, if it can get heat from the outside world, it will never be able to freeze.
Alcohol just provides such a condition, it is far from possible to reach the coagulation state in the refrigerator at -5 °, it will only continue to release heat, but it can never reach -117 °, that is, it cannot reach the freezing point, so alcohol and water are always liquid and cannot be separated.
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Anonymous users2024-02-12Answer: After putting the mixture into the freezer room of the refrigerator with a temperature of -5, the water did not solidify and the alcohol could not be separated Hypothesis: The water contains alcohol, and the freezing point of the water is reduced
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Anonymous users2024-02-11For the same kind of crystal, its melting point and freezing point are the same, so the freezing point of water is 0, and the freezing point of alcohol is -117, because the freezing point of water is high, so when cooling, the temperature first drops to the freezing point of water, and the water solidifies into ice, which is separated first
Therefore, choose B
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Anonymous users2024-02-10For the same kind of crystal, its melting point and freezing point are the same, so the freezing point of water is 0, and the freezing point of alcohol is -117, because the freezing point of water is high, so when cooling, the temperature first drops to the freezing point of water, and the water solidifies into ice, which is separated first
Therefore, choose B
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