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What property of a particular solute towards a solvent is necessary for recrystallization to occur?
Wiki User
∙ 12y ago
The coolness of the solution causes recrystallization. This is because the solute becomes solid at a higher temperature than the solvent.
Wiki User
∙ 9y ago
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What are the desirable properties of a recrystallization solvent?
Desirable properties of a recrystallization solvent include high solubility for the compound at high temperatures and low solubility at lower temperatures to facilitate crystal formation, non-reactivity with the compound being purified, easy removal after recrystallization, and low toxicity.
How do you prevent immature recrystallization?
To prevent immature recrystallization, ensure that the solvent is added slowly to the solution during recrystallization, use a minimal amount of solvent, and employ a suitable solvent system based on the solubility of the compound. Additionally, controlling the rate of cooling during recrystallization can help prevent premature crystallization of impurities.
What is the recyrstallization solvent for benzocaine?
Common recrystallization solvents for benzocaine include ethanol and ethyl acetate. The choice of solvent will depend on the solubility of benzocaine in the solvent at different temperatures. It is recommended to perform a solubility test to determine the most suitable solvent for recrystallization.
What solvent is used to recrystallize the salicylic acid?
Ethanol is commonly used as a solvent to recrystallize salicylic acid due to its ability to dissolve the compound at high temperatures and then allow for recrystallization as it cools.
What is the purpose of the sublimation and recrystallization steps?
Sublimation is used to purify compounds by separating them from impurities through the phase transition from solid to gas. Recrystallization is employed to purify a solid compound by dissolving it in a solvent, removing impurities, and then allowing the compound to crystallize back out in a purer form.
What are the desirable properties of a recrystallization solvent?
Desirable properties of a recrystallization solvent include high solubility for the compound at high temperatures and low solubility at lower temperatures to facilitate crystal formation, non-reactivity with the compound being purified, easy removal after recrystallization, and low toxicity.
How do you prevent immature recrystallization?
To prevent immature recrystallization, ensure that the solvent is added slowly to the solution during recrystallization, use a minimal amount of solvent, and employ a suitable solvent system based on the solubility of the compound. Additionally, controlling the rate of cooling during recrystallization can help prevent premature crystallization of impurities.
What is the recyrstallization solvent for benzocaine?
Common recrystallization solvents for benzocaine include ethanol and ethyl acetate. The choice of solvent will depend on the solubility of benzocaine in the solvent at different temperatures. It is recommended to perform a solubility test to determine the most suitable solvent for recrystallization.
Is Chloroform a good solvent for recrystallization in acetanilide?
Chloroform is not a commonly used solvent for recrystallization of acetanilide. It is more commonly used for dissolving non-polar or slightly polar compounds. In the case of acetanilide, solvents such as ethanol or ethyl acetate are often preferred for recrystallization.
What is the disadvantage of having excess solvent during recrystallization?
Having excess solvent during recrystallization can result in a lower concentration of the desired compound in the final crystal product. This can reduce the purity of the compound and make it more difficult to separate from impurities. Additionally, excess solvent can increase the time required for the recrystallization process to complete.
Why is the product formed from recrystallization sometimes contaminated with impurities?
The product formed from recrystallization can be contaminated with impurities if they are more soluble in the solvent used for recrystallization compared to the desired compound. In this case, the impurities will remain in the solution while the desired compound forms crystals, leading to impurity inclusion in the final product. Proper choice of solvent and recrystallization conditions can help minimize impurity contamination.
What is a good solvent for recrystallization of sodium benzoate?
A good solvent for recrystallization of sodium benzoate is water, as sodium benzoate is highly soluble in water. Additionally, ethanol can also be used as a co-solvent to enhance solubility and increase the purity of the recrystallized product.
When doing a solvent pair recrystallization which of the following pairs will work ethanol and water methylene chloride and water dimethylformamide and diethyl ether?
Ethanol and water is a suitable solvent pair for recrystallization. Methylene chloride and water, as well as dimethylformamide and diethyl ether, are not typically used together as solvent pairs for recrystallization due to their different chemical properties and solubility characteristics.
Why ethanol is the best solvent for recrystallization of urea?
Ethanol is a good solvent for recrystallization of urea because it has the ability to dissolve urea at higher temperatures and allows for selective precipitation at lower temperatures, resulting in purer crystals. Additionally, ethanol is a relatively non-toxic solvent and is readily available, making it a practical choice for recrystallization processes.
Explain why during the recrystallization of p-dibromobenzene the turbidity of the hot solution was used as an indicator for the ratio of ethanol to water used?
The turbidity of the hot solution during recrystallization can indicate the saturation level of the solvent system. If the solution becomes turbid at a certain ratio of ethanol to water, it suggests that the solvent system is nearing its saturation point for dissolving the compound. This can help determine the ideal solvent ratio for recrystallization to achieve maximum yield and purity of the compound.
Is benzhydrol suitable for recrystallization of bezhydrol?
Yes, benzhydrol can be suitable for recrystallizing benzhydrol. Recrystallization is a common technique used to purify solid compounds by dissolving them in a suitable solvent and allowing them to slowly crystallize out. It is important to choose a solvent in which the compound is more soluble at high temperatures and less soluble at low temperatures to achieve successful recrystallization.
Solvent for recrystallization?
A good solvent for recrystallization depends entirely on the polarity of the solid you're trying to purify. For example sodium chloride readily dissolves in water whereas naphthalene dissolves only in nonpolar solvents like hexane. To select a good solvent first consider the polarity of the compound of interest and pick a solvent that has the potential to dissolve it. Next suspend the solid in that solvent. You must pick another solvent if the solid completely dissolves in the selected solvent. Heat the mixture while stirring. If you reach the boiling point of the solvent and the compound hasn't dissolved, you must find a different solvent or add more of the solvent you are currently using. If your solid completely dissolves without too much of the chosen solvent, you have yourself a good solvent for recrystallization. To continue with the recrystallization simply allow the solvent to cool and your solid should precipitate out in the form of crystals. Put it in an ice bath to assist with the precipitation. The latter technique can lead to small crystals or powder. The best way to remedy this is to do a slow recrystallization. To do this you must use two solvents that will evaporate over a long period of time. One solvent must be very volatile and must be able to easily dissolve your compound at room temp. The other must be less volatile and your compound must be insoluble in this solvent. Note that this solvent must have the potential for dissolving the impurities in your compound. To perform the recrystallization, dissolve your compound in the "good" solvent and then add about the same amount of the "bad" solvent. Over a period of time, the "good" solvent should evaporate leaving your crystallized product in the "bad" solvent without any impurities.
