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The potassium nitrate solution is mixed with sodium chloride and purified by evaporation, crystallization and hot filtration, right? Why? Thank you. What is recrystallization? Xie~~
True, recrystallization is the process of dissolving the crystal in the solvent and then recrystallizing from the solution or the melt. The solubility of potassium nitrate is greatly affected by the temperature. The solubility of potassium nitrate is similar at normal temperature. When the temperature is high, the solubility of potassium nitrate is much higher than that of sodium chloride. The sodium chloride precipitates first, so that the sodium chloride can be filtration.
True, recrystallization is the process of dissolving the crystal in the solvent and then recrystallizing from the solution or the melt. The solubility of potassium nitrate is greatly affected by the temperature. The solubility of potassium nitrate is similar at normal temperature. When the temperature is high, the solubility of potassium nitrate is much higher than that of sodium chloride. Sodium chloride precipitates first, so that sodium chloride can be removed by filtration.
True, recrystallization is the process of dissolving the crystal in the solvent and then recrystallizing from the solution or the melt. The solubility of potassium nitrate is greatly affected by the temperature. The solubility of potassium nitrate is the same at normal temperature. When the temperature is high, the solubility of potassium nitrate is much higher than that of sodium chloride. The sodium chloride precipitates first, so that the sodium chloride can be filtration.
A small amount of potassium nitrate mixed in NaCl can be purified by evaporative crystallization, but can NaCl be completely purified? Why? Doesn't potassium nitrate precipitate when water is evaporated to a certain degree
Potassium nitrate is applicable when the impurities are relatively small. Water evaporation generally requires heating, and the solubility of potassium nitrate is also increased leaving a small amount of solvent potassium nitrate will not become crystal and precipitate, so it can be removed
Potassium nitrate is suitable for less impurities. Water evaporation generally requires heating, and the solubility of potassium nitrate also increases. A small amount of solvent, potassium nitrate, will not become crystal and precipitate, so it can be removed
RELATED INFORMATIONS
- 1. What does cooling crystallization purify?
- 2. Why the potassium nitrate solution contains a small amount of sodium chloride should be purified by cooling crystallization method Why not use evaporative solvents? Is sodium chloride or potassium nitrate separated out? After meeting the question about purification, what kind of separation is it?
- 3. How to purify potassium nitrate if potassium nitrate contains a small amount of sodium chloride (1 dissolution 2 filtration 3 cooling crystallization 4 heating and concentration) and explain the principle
- 4. Will the solubility of the substance change while the solvent is being evaporated?
- 5. What is the relationship between the solubility curve and evaporation crystallization or cooling crystallization? Is, for example, a solubility that increases with temperature Many, the other little change, this and other types of what crystal removal methods are needed
- 6. What is the characteristic of the solubility of various solid substances affected by temperature?
- 7. Why does the solubility of a gas solid vary with temperature, since it diffuses uniformly in molecular or ionic form after dissolution? Should we consider micro rather than macro at this point? Why does the solubility of a gas solid vary with temperature, since it diffuses uniformly in molecular or ionic form after dissolution? Should microcosmic, not macrocosmic, be considered at this point?
- 8. At t.degree. C.,500 g of potassium nitrate solution,40 g of water evaporated,20 g of crystals precipitated, and 40 g of crystals precipitated after further evaporation of 40 g of water How much is the solubility at this temperature?
- 9. A solution of substance A was evaporated to 20 g of water at a constant temperature to precipitate 2 g of crystal A. (1) At t°C, the solution of substance A evaporates 20 g of water at a constant temperature, precipitates 2 g of crystal A, and evaporates 20 g of water again at a second time at a constant temperature resulting in the precipitation of 8 g of crystal A, and the solubility of substance A at t°C. (2) To obtain crystals from lime water, the () method is usually used because () A solution of substance A was evaporated to 20 g of water at a constant temperature to precipitate 2 g of crystal A. (1) At t°C, the solution of substance A evaporates 20 g of water at a constant temperature, precipitates 2 g of crystal A, and evaporates 20 g of water at a second time at a constant temperature, resulting in the precipitation of 8 g of crystal A, and the solubility of substance A at t°C. (2) To obtain crystals from lime water, the () method is usually used because ()
- 10. T°C is the solution of KNO3(potassium nitrate). When A g of water is evaporated at constant temperature, a g of crystal is precipitated; To re-evaporate A g of water and precipitate b g of crystal (a not equal to b), answer the following questions: (1) The size of a and b. (2) What is the solubility of potassium nitrate at T°C? T°C is the solution of KNO3(potassium nitrate). When A g of water is evaporated at constant temperature, a g of crystal is precipitated; To re-evaporate A g of water and precipitate b g of crystal (a is not equal to b), answer the following questions: (1) Size of a and b. (2) What is the solubility of potassium nitrate at T°C?
- 11. If the potassium nitrate solution contains a small amount of sodium chloride, it can be purified by evaporative crystallization 1. The remaining solution must be potassium nitrate solution 2. The remaining solution must be sodium chloride unsaturated solution 3. The above method can completely separate the two 4. Precipitated crystals contain only potassium nitrate If the potassium nitrate solution contains a small amount of sodium chloride, it can be purified by evaporative crystallization 1. The remaining solution must be potassium nitrate solution 2. The remaining solution must be sodium chloride unsaturated solution 3. The above method can completely separate the two. 4. Precipitated crystals contain only potassium nitrate
- 12. Who tells me the difference and principle between evaporative concentration, cooling crystallization and evaporative concentration, hot filtration? The teacher said that "evaporative concentration, cooling crystallization" is used for substances whose solubility varies greatly with temperature, such as KNO3. But what is the principle of it? Who comes out and who stays in the solution? Why can "evaporative concentration, cooling crystallization" purify substances whose solubility varies greatly with temperature? Give me a detailed example. Also talk about evaporating and concentrating, filtering while hot A lot of wrong answers on the Internet ~ I hope you don't talk nonsense.
- 13. Why filter after high-medium chemical evaporation concentration cooling crystallization? Mother liquor should be only water ~ and why wash? Doesn't the purified product dissolve after washing? Why ethanol? How does it dry in the end? The original topic is evaporative concentration while hot filtration cooling crystallization after why filtration! Why filter after high-medium chemical evaporation concentration cooling crystallization? Mother liquor should be only water ~ and why wash? Doesn't the purified product dissolve after washing? Why ethanol? How did it dry out? The original topic is evaporative concentration while hot filtration cooling crystallization after why filtration! Why filter after high-medium chemical evaporation concentration cooling crystallization? Mother liquor should be only water ~ and why wash? Doesn't the purified product dissolve after washing? Why ethanol? How does it dry in the end? The original problem is evaporative concentration while hot filtration cooling crystallization after why filtration!
- 14. What is the difference between evaporative crystallization and evaporative concentration cooling crystallization filtration? What should I use to get crystals with crystalline water
- 15. What is concentrated crystallization and what is the difference between concentrated crystallization and cooling, evaporative crystallization?
- 16. Evaporate the unsaturated solution until crystals begin to precipitate and stop heating. The resulting solution is As above. Saturated solution or unsaturated solution? Why? Evaporate the unsaturated solution until crystals begin to precipitate and stop heating. The resulting solution is As above. Saturated solution or unsaturated solution? Why? Why?
- 17. At 20°C, put 20g of sodium chloride into 100g of sodium chloride to prepare unsaturated solution. To saturate the solution, how many grams of sodium chloride need to be evaporated or how many sodium chloride crystals need to be added (The solubility of sodium chloride at 20.degree. C. is known to be 36 g At 20°C, put 20 g of sodium chloride into 100 g of sodium chloride to prepare an unsaturated solution. To saturate the solution, how many grams of sodium chloride need to be evaporated or how many sodium chloride crystals need to be added (The solubility of sodium chloride at 20.degree. C. is known to be 36 g
- 18. To obtain salt crystals from a salt solution, the method can be A Decreasing temperature B Increase pressure C Evaporating solvent D Filtering
- 19. Is it certain that crystals will precipitate from the unsaturated solution after a period of evaporation? Why?
- 20. What is the crystallization process of unsaturated solution What is the process of crystal precipitation in unsaturated solution