Question

Extraction

Q1. Why doesn’t the neutral organic compound dissolve in the 1.5 M NaOH solution?

Q2. Why is diethyl ether a good choice for the organic solvent in this extraction experiment?

Q3. What experimental difficulty would you encounter if you neglected to include the drying step before evaporating the ether solution of the neutral organic compound?

Q4. Why are the two organic compounds recrystallized before their melting points are determined?

Q5. What IR bands are most useful in distinguishing a carboxylic acid from a neutral organic compound?

Q6. Describe the characteristics of a good recrystallization solvent.

Grignard Reagent Experiment

Q1. Benzene is often a by-product in the synthesis of phenylmagnesium bromide. Explain its formation, including a chemical reaction.

Q2. If a chemist uses ethanol instead of diethyl ether as the reaction solvent, would the Grignard synthesis still proceed as expected?

Q3. What is the structure of the white precipitate that forms when acetophenone is added to a solution of phenylmagnesium bromide?

Q4. An aqueous ammonium chloride solution, rather than sulfuric acid, is used in the hydrolysis of the magnesium complex of 1,1-diphenylethanol to ensure that no acid-catalyzed dehydration occurs. Write the chemical structure of the dehydration product from 1,1-diphenylethanol.

Q5. If acetone were reacted with phenylmagnesium bromide, followed by hydrolysis of the intermediate magnesium complex, what would the organic product be?

Other

•         Acid-base proton transfers: Know how this type of reaction is used in extraction to separate organic compounds. How is solubility used to your advantage to make this work? For practice, try drawing a flow chart (similar to the one we drew in lab) showing how to separate and isolate a carboxylic acid, a neutral, and an amine.

Extraction

Q1. Why doesn’t the neutral organic compound dissolve in the 1.5 M NaOH solution?

Q2. Why is diethyl ether a good choice for the organic solvent in this extraction experiment?

Q3. What experimental difficulty would you encounter if you neglected to include the drying step before evaporating the ether solution of the neutral organic compound?

Q4. Why are the two organic compounds recrystallized before their melting points are determined?

Q5. What IR bands are most useful in distinguishing a carboxylic acid from a neutral organic compound?

Q6. Describe the characteristics of a good recrystallization solvent.

Grignard Reagent Experiment

Q1. Benzene is often a by-product in the synthesis of phenylmagnesium bromide. Explain its formation, including a chemical reaction.

Q2. If a chemist uses ethanol instead of diethyl ether as the reaction solvent, would the Grignard synthesis still proceed as expected?

Q3. What is the structure of the white precipitate that forms when acetophenone is added to a solution of phenylmagnesium bromide?

Q4. An aqueous ammonium chloride solution, rather than sulfuric acid, is used in the hydrolysis of the magnesium complex of 1,1-diphenylethanol to ensure that no acid-catalyzed dehydration occurs. Write the chemical structure of the dehydration product from 1,1-diphenylethanol.

Q5. If acetone were reacted with phenylmagnesium bromide, followed by hydrolysis of the intermediate magnesium complex, what would the organic product be?

Other

•         Acid-base proton transfers: Know how this type of reaction is used in extraction to separate organic compounds. How is solubility used to your advantage to make this work? For practice, try drawing a flow chart (similar to the one we drew in lab) showing how to separate and isolate a carboxylic acid, a neutral, and an amine.

Extraction

Q1. Why doesn’t the neutral organic compound dissolve in the 1.5 M NaOH solution?

Q2. Why is diethyl ether a good choice for the organic solvent in this extraction experiment?

Q3. What experimental difficulty would you encounter if you neglected to include the drying step before evaporating the ether solution of the neutral organic compound?

Q4. Why are the two organic compounds recrystallized before their melting points are determined?

Q5. What IR bands are most useful in distinguishing a carboxylic acid from a neutral organic compound?

Q6. Describe the characteristics of a good recrystallization solvent.

Grignard Reagent Experiment

Q1. Benzene is often a by-product in the synthesis of phenylmagnesium bromide. Explain its formation, including a chemical reaction.

Q2. If a chemist uses ethanol instead of diethyl ether as the reaction solvent, would the Grignard synthesis still proceed as expected?

Q3. What is the structure of the white precipitate that forms when acetophenone is added to a solution of phenylmagnesium bromide?

Q4. An aqueous ammonium chloride solution, rather than sulfuric acid, is used in the hydrolysis of the magnesium complex of 1,1-diphenylethanol to ensure that no acid-catalyzed dehydration occurs. Write the chemical structure of the dehydration product from 1,1-diphenylethanol.

Q5. If acetone were reacted with phenylmagnesium bromide, followed by hydrolysis of the intermediate magnesium complex, what would the organic product be?

Other

•         Acid-base proton transfers: Know how this type of reaction is used in extraction to separate organic compounds. How is solubility used to your advantage to make this work? For practice, try drawing a flow chart (similar to the one we drew in lab) showing how to separate and isolate a carboxylic acid, a neutral, and an amine.

Extraction

Q1. Why doesn’t the neutral organic compound dissolve in the 1.5 M NaOH solution?

Q2. Why is diethyl ether a good choice for the organic solvent in this extraction experiment?

Q3. What experimental difficulty would you encounter if you neglected to include the drying step before evaporating the ether solution of the neutral organic compound?

Q4. Why are the two organic compounds recrystallized before their melting points are determined?

Q5. What IR bands are most useful in distinguishing a carboxylic acid from a neutral organic compound?

Q6. Describe the characteristics of a good recrystallization solvent.

Answer 1

Q1=>Neutral compound does not react with base it will go in organic phase only .The compound which is acidic in nature only will react with base and forms it's salt.So neutral compound will not dissolves in1.5 M NaOH solution.

Q2=> Ether is an Volatile solvent and forms an upper layer when we mixed it with water layer .it is easy to evaporate.

Q3=>If we did not dry the organic ether layer with anhydrous sodium sulphate it may have traces of water present and will encounter in actual yield of the product. And compound may not be fully dried it may have some water contain.

Q4=> Recrystallization is necessary because then and then only you will end up with the pure product. If compound is not pure enough it encounter in melting point . melting point may may vary from it's original melting point range. Mixture of compound will have different melting point.

Q5=>Carboxylic acid IR frequency will come around 2800 to 3500cm-1 and neutral molecule will not be in the same region.

Q6=> Good Recrystallization solvent is solvent which can dissolves the organic compound in minimum amount at it's boiling point and low boiling in nature .also it should not interfere with compound.