Answered: Why is it important to pull air through…

Why is it important to pull air through the crystals for 5-10 minutes after washing with 95% ethanol? If this step was omitted, what might you see in the IR?

Macroscale and Microscale Organic Experiments

7th Edition

ISBN:9781305577190

Author:Kenneth L. Williamson, Katherine M. Masters

Publisher:Kenneth L. Williamson, Katherine M. Masters

Chapter4: Recrystallization

Section: Chapter Questions

Problem 8Q

See similar textbooks

Related questions

Q: What is deionized water? What kind of impurities are not removed by deionization?

A: Purified water does not contain any impurity. There are various methods for purification of water…

Q: Write the principle behind the froth floatation process. What is the role of collectors in this…

A: Various processes are used for extraction of minerals. These minerals are very useful for…

Q: Why was gravity filtration used instead of evaporation to isolate the calcium carbonate?

A: Calcium Carbonate is white, odorless powder or colorless crystals. Practically insoluble in water.…

Q: 9) If after drying, the TLC plate showed spot A showed a Rf of 0.20 and spot B showed a Rf of 0.22.…

A: During the detection and separation of components in a compound using TLC, the solvent front is kept…

Q: Student A did not see any spots on her TLC plate after visualization under iodine vapor. Which of…

A: The solution is given below -

Q: Explain how the Rf (Retention Factor)-values can be in agreement or disagreement with the “like…

A: Interpretation - To explain all about that how the Rf ( Retention factor ) - values can be…

Q: Why should a piece of filter paper inside the developing chamber be moistened with the developing…

Q: if you wanted to extract 15mL of an aqueous layer, why wouldn’t you want to use 45mL of the organic…

A: The technique which is used to separate the organic compounds from aqueous is called "Differential…

Q: What would happen if we use longer columns and select adsorbing materials with 200-400 mesh sizes…

A: Solution is given in the following steps:

Q: Why mixture of solvents such as ethyl acetate with 5% acetic acid is used as a solvent/mobile phase…

A: TLC (Thin layer chromatography) is a technique to separate the components of mixture. TLC uses a…

Q: Vaccum filtration is the major technique used in this experiment. The following step sequences are…

A: The vacuum filter may be described as the approach which is basically used to disparate the solid…

Q: Why is it necessary to run TLC in a closed container and to have the interior vapor saturated with…

A: In the separation of compounds by TLC, a solvent moves the compound up the plate based on its…

Q: What are the considerations for choosing the solvent in the extraction?

A: Given: Considerations for choosing the solvent in the extraction.

Q: a) Discuss the effect of solvent polarity on Rf-values. b)Explain how the Rf (Retention…

A: Since you have posted two questions, we will solve first question for you. Please repost other…

Q: Characterize TLC plate, R, Explain the parotic and aprotic solvents, give example. In the case of…

A: TLC stands for thin layer chromatography. It is an chromatography technique which is used to…

Q: Why do we need to add sand on top of the silica in column chromatography? What could happen if we…

A: The presence of different compounds in the mixture is separated by employing the separation methods.…

Q: Why is the final product from recrystallization isolated by vacuum filtration and not by gravity…

Q: Outline the principle of the supercritical fluid chromatography technique .

A: Supercritical fluid chromatography encompasses all chromatographic methods in which the mobile phase…

Q: What will be the appearance of a TLC plate if a solvent of too low polarity is used for the…

A: Thin layer chromatography is a technique which is used for the separation of components of a…

Q: Demonstrate how to make TLC, and analyze the sample for any purpose, which deemed suitable for you

A: TLC is a thin layer chromatography, a technique used for separating non-volatile mixtures and…

Q: Give Four main precautions need to be considered when carrying out the following.

A: ANSWER IS :

Q: look for at least three extraction methods for perfumery materials.

A: There are several methods which are used for extraction of the perfumery materials from different…

Q: If insoluble impurities eg. dust, tissues, filter paper etc were mixed with the sample how will…

A: Melting Points:- The melting point of a substance is defined as the temperature at which it melts.…

Q: Based on the thin layer chromatography experiment what should be considered when choosing the right…

A: Thin layer chromatography is one of the conventional technique for the separation of constituents in…

Q: 10. If an eluent of too high polarity is used for the development of a TLC plate, will the sample…

A: The TLC plate have the stationary phase Silica and Mobile phase which is solvent . Solvent may be…

Q: How would the Rf values change if you used pure dichloromethane (no methanol) as the mobile phase…

A: The dielectric constant for methanol is 30 and that of Dichloromethane is 8.3

Q: What would be the effect of increasing the carrier gas flow rate on the retention rate?

A: Retention time is the distance that the compound cover from the time of injection till the maxima in…

Q: Vhat criteria should you use to determine the solvent for dissolving a sample for TLC analysis? Vhat…

A: the solvent should be 2-3 mm deep so that the spotted sample and the line are not submerged this…

Q: Explain the function of using dichloromethane after the steam extraction of Eugenol. Also discuss if…

A: Answer - During the process, Eugenol is extracted from the distillate with dichloromethane and…

Q: What adsorbents can be used to remove impurities from benzoic acid? Explain the molecular basis for…

A: Benzoic acid is an organic compound. Therefore, the impurities that remain dissolved in benzoic acid…

Q: Before applying the eluent on the column, why is it important to drain the solvent to a level right…

Q: Describe how you would prepare a sample for TGA analysis if it were provided in the form of: (i)…

A: Thermogravimetric analysis (TGA) of polymers is conducted to measure weight changes as a function of…

Q: In liquid, extraction, why is it necessary to turn the separatory funnel upside down and to open the…

A: Liquid-liquid extraction is also called solvent extraction is a method of separating compound from…

Q: When would you choose to run a TLC? Choose all that apply. to determine if a sample is pure to…

A: Thin layer chromatography (TLC) is a separation technique using a small quantity of the sample.

Q: Jamar spotted the three (3) component mixture shown below to a TLC plate and developed it using the…

Q: Why is a filter paper preferred over a sintered glass filter?

A: Filtered paper is made up of fiber and there are numerous holes (obviously of microscopic size) in…

Q: 1.What is the purpose of washing the recrystallized solid with solvent during the vacuum filtration…

A: A question based on purification, which is to be accomplished.

Q: why should a small volume of the cold solvent be used for rinsing the pure crystal?…

A: Using a cold solvent, the impurities present in the surface of pure crystal is removed by rinsing…

Q: Why ink must never be used to mark the TLC (Thin-Layer Chromatography) plate?

A: Thin chromatography plate is very commonly used in industries for identifying of a compound . Purity…

Q: What is the order in which the following compounds would he eluted from an HPLC column containing a…

A: To find: The order of elution of the given compounds in HPLC

Q: Why is it important to see the level of solvent in the developing chamber when running a TLC…

A: It is extremely important that the solvent in the developing chamber be lower than the spots on the…

Q: After acid-base extraction why is it important to wash organic layer at least once with pure water?

A: A question based on quantitative analysis, which is to be accomplished.

Q: How does increasing the polarity of the developing solvent affect the Rf of a compound on a silica…

A: TLC stands for Thin Layer Chromatography. This process is basically used for the differentiation of…

Q: You are about to purify an impure sample of naphthalene by column chromatography. What solvent…

A: Column chromatography is an analytical method used for the separation of a compound from the mixture…

Q: 3. Compound A has an Rf of 0.75 and compound B has an Rf of 0.35. Which compound will elute first…

Q: 1.what data must be available when HPLC method is passed on 2.why eluents should be degassed

A: 1.data needed for HPLC: HPLC is High performance liquid chromatography. Chromatography: It is a…

Q: Why do you think there is a need to soak the crucible with 10% nitric acid for preparation in dry…

A: An analytical technique in which the sample's composition is being evaluated and the sample remains…

Q: If insoluble impurities, e.g., dust, tissue, filter paper, etc., were mixed with the sample, how…

A: Insoluble impurities The term "insoluble impurities" refers to contaminants that settle or float on…

Q: Why might it be very difficult to visualize the separation of cis- and trans-2-butene by TLC?

A: Structures of 2-butene isomers are given below,

Question

Why is it important to pull air through the crystals for 5-10 minutes after washing with 95%
ethanol? If this step was omitted, what might you see in the IR?

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

This is a popular solution!

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Trending now

This is a popular solution!

Step by step

Solved in 2 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.

Similar questions

Of Aspirin, ethanol, acetaminophen, ethyl acetate, hexane, and water which could go undetected during HPLC analysis, but could result in a lower than expected melting point, why are they not detected by HPLC analysis?
Why is it required to add drying agent like sodium sulphate to the organic layer which may contain only a neutral compound? Explain
What adsorbents can be used to remove impurities from benzoic acid? Explain the molecular basis for your choice.
If insoluble impurities, e.g., dust, tissue, filter paper, etc., were mixed with the sample, how would these affect the measured melting point?
Some procedures include the addition of sodium carbonate before liquid-liquid extraction. What is the purpose of this step?
1.What is the purpose of washing the recrystallized solid with solvent during the vacuum filtration step? Why should the solvent be cold?
Vaccum filtration is the major technique used in this experiment. The following step sequences are recommended: 1) turn on vacuum 2) wet the filter paper and 3) pour the product solution into the buchner funnel. can the Vacuum be turned on in the last step instead?explain
In the video (liquid-liquid extraction), why is it necessary to turn the separatory funnel upside down and to open the stopcock?
Why is it necessary to run TLC in a closed container and to have the interior vapor saturated with the solvent? What error is introduced into the determination of an Rf value if the top is left off of the developing chamber?
1. Why does the solid need to be finely ground and then tightly packed in a melting point capillary tube?
Why is sodium chloride added before extraction the aqueous layer with DCM? How does magnesium sulfate break emulsions?
Explain the function of using dichloromethane after the steam extraction of Eugenol. Also discuss if there are any differences and which ones in soxhlet extraction and steam drag.