answer

watching

views

11 Dec 2019

3. More reaction conditions... Which one of the following choices describes most accurately the actual, internal reaction temperature (in other words, the temperature of the reaction mixture inside the reaction vial) for this Fischer esterification? Select one (include the letter AND answer in your response), and explain your answer. a) Boiling point of n-butyl acetate (124-126 Â°C) b) Boiling point of acetic acid (117 Â°C) c) Boiling point of 1-butanol (116-118 Â°C) d) Boiling point of the reaction mixture (reflux temperature) e) Sand bath temperature (160-180 Â°C)

answer

watching

401

views

For unlimited access to Homework Help, a Homework+ subscription is required.

You have 0 free answers left.
Get unlimited access to 3.8 million step-by-step answers.

Get unlimited access

Already have an account? Log in

Trinidad TremblayLv2

13 Dec 2019

Unlock all answers

Get 1 free homework help answer.

Already have an account? Log in

Join us on Discord

Chemistry Study Group

Join now

Related questions

Which one of the following choices describes most accurately the actual, internal reaction
temperature (in other words, the temperature of the reaction mixture inside the reaction vial)
for the Fischer esterification experiment of 1-butanol with acetic acid to form n-butyl acetate? Select one, and explain your answer.
a) Sand bath temperature (160-180 Â°C)
b) Boiling point of 1-butanol (116-118 Â°C)
c) Boiling point of the reaction mixture (reflux temperature)
d) Boiling point of acetic acid (117 Â°C)
e) Boiling point of n-butyl acetate (124-126 Â°C)

How to create a table of reagents with the information given. Ester of choice is isoamyl acetate

7. SYNTHISIS OF FRUITY ESTERS USING THE FISCHER ESTERIFICATION REACTION H2504 (cat) soamyl alel acetic acie H-S04 (cat) n-butanolaccid H2504 (cat) the chemistry of fragrances, chemical equilibria Experimental techniqees: Microscale reflux, NMR, microscale aqueous extraction Adapted from: Palleros, P. K etal "Microscale Organic Laboratory". p. 480. Befone he lab period pick one of the esters drawn ahove. If you work in a team, try to coordinate this with your teammate befosehand. If you don't do this in time for the lab, then just worry about it when you get to lab, and then copy(and double-check) the rclevant dataãquestions 3a and 3b) for the ester you decide to make with your partner 2. Prepare your pre-experiment notcbook entry (lowchart, table of reagents with physical constamts, etc) 3. Answer the following questions: For only the ester you are making, please draw a dctailed clectron-pushing mechanism to show the formation of compound. There are many sesources available to you on the web, etc) fr the mechamism of the Fischer esterification reaction a. b. You will start with 500 mg of one of your starting alcohel(whichever one you will be using to gencrate your product). While the acohols are liquids, we will measure them by mass directly on the balance, no by volume (ie. the density of the alcohol will not be used: pretend the alcohol is a solid). Acetic acid (or propionic acid) will be mcasured by volume. Delermine the volume of acetic acid (or propionic acid) to add that will correspond to 40 molar equivalents based on mmols of starting c. Considering that the reaction produces water in the mechanism (question a), what reagents could be added to the reaction mixture to enhance coeversion to product? (Think of a specific Reaction Inlo 10 ml RBF, add the aleohol you chose (500 mg), acetie acid or peopionie acid (alulated quantity, by pluringe, and cone, sulfuric acid (3äº ops, no more). Do not spill conc, sulfuric acid on yourself! 2. Altach (screw on) a microscale condenser (with rubber O-ring seall) to the RBF, and flow water through You can the bottom of the condenser. Be very careful when tuming the water on to avoid a waler spill then directly clamp the condenser and have the RBF suspended it into the sand bath Heat the reaction mixture in a sand bath to a gentle boil (roughly-130-140â, but it varies for each experiment) for 45 min, and them allow the mixture to cool to necarly ambient temperature 3. Workup and purification Transfer the reaction mixture by pipette from the RBF to a 4 ml conical vial 5. Rinse the residual reaction misture from the RBF to the cotical vial using 2 ml 5% NaHCO/19% NaCl 6. Cap the tube and invert it several times to mix the layers. Vent the tube as necessary, Allow the layers 7. Wash the product with additional 5% NaHCO,19% NaCI

Please help me with the following problem. It has many parts to it, but it is one question. Thank you in advance

Synthesis of 1-Bromobutane

Reaction Scheme

NaBr, H2SO4

CH3CH2CH2CH2OH---------------------> CH3CH2CH2CH2Br + NaHSO4 + H2O

H2O

Possible by-products:

1-butene (bp â6.3 ^oC), di-n-butyl ether, C₄H₉OC₄H₉, (bp 141 ^oC)

Properties of reagents and product:

Substance	Mol Wt. (g/mol)	Density (g/ml)	bp, ^oC	Solubility	Hazards
1-butanol	74.12	.81	117-118	Sol water, Miscible alc, ether, and more	Flammable, irritant
H₂SO₄ (con)	98.07	1.84	280	X	corrosive material
sodium bromide	102.89	X	X	X	X
1-bromobutane	137.03	1.27	101.6	Insol in water; sol in alcohol, ether	Flammable, irritant

Quantities used in the reaction and yield data:

Substance	g or mL	Calculated moles	Theoretical Yield moles grams		Actual Yield, grams
1-butanol	mLs		x	x	x
H₂SO₄ (con)	11.5 mL		x	x	x
sodium bromide	13.3 g		x	x	x
Water	15.0 mL	x	x	x	x
1-bromobutane	x	x			Want 7.5 g

A. Assume the above synthesis of 1-bromobutane is known to proceed in 75% yield and you would like to prepare 7.5 g of material. Back calculate how many mLs of 1-butanol you will need for the reaction to synthesize the 7.5 g of product, assuming that the 1-butanol is the limiting reagent. Place this number in the table. Also, calculate all the remaining missing data to fill the table.

Experimental Procedure: The NaBr, 1-butanol, and water are combined in a round-bottomed flask containing a stir bar and cooled to 0 ^oC. Concentrated sulfuric acid is slowly added with stirring. The reaction flask is then prepared for a 50-minute âbriskâ reflux using a heating mantle. After reflux, two layers will be present. The condenser is removed and replaced with a distillation apparatus. Distill the mixture, recording the temperature range, until no more water- insoluble droplets are collected and the temperatures reaches around 115 ^oC. (The boiling point is elevated due to azeotropic distillation of the water with the 1-bromobutane and increasing amounts of sulfuric acid).

B. Propose a way that you could test if the droplets coming over are âwater-insolubleâ.

Be specific with the manipulations, glassware, and what observation you would see.

The collected liquid is transferred to a separatory funnel and 10 mL of water is added. Two layers form, the bottom being the 1-bromobutane layer. The layers are separated, one through the bottom and one through the top, and the separatory funnel is cleaned and dried. The bromobutane layer is returned to the separatory funnel and washed with ice-cold sulfuric acid to remove traces of the starting material, butene and ethereal by-products.

C. Will the top or bottom layer be the bromobutane layer when washing with concentrated sulfuric acid? Why?

The sulfuric acid layer is removed and the 1-bromobutane is washed with 10 mL 3 M NaOH followed by 10 mL aqueous sodium chloride (brine).

D. What is the purpose of each of these washes?

NaOH â

Brine -

Care should be taken to save the correct layer. The 1-bromobutane is then dried over anhydrous CaCl₂.

E. How will you decide how much drying agent to use? How will you know that the 1-bromobutane is dry.

The product is distilled to obtain a clear, colorless liquid.

F. TLC â Suppose you wanted to follow the above reaction by TLC.

a. Describe how you would go about finding a good solvent or solvent pair to use.

b. Suggest a specific solvent system you would try.

c. Draw below what you would want the TLC plate to look like and show the expected relative R_f values for the 1-butanol and 1-bromobutane. Label the spots, baseline, and solvent front.

Weekly leaderboard

Home

Homework Help 3,900,000

Chemistry 830,000

Unlock all answers

Related textbook solutions

Basic Chemistry

Principles of Chemistry Molecular Approach

Chemistry: Structure and Properties

Principles of Chemistry Molecular Approach

Chemistry: A Molecular Approach

Chemistry: A Molecular Approach

Principles of Chemistry: A Molecular Approach

Chemistry: The Central Science

Related questions

Weekly leaderboard