Extraction of Benzoic Acid

Introduction: The theory behind the extraction of a solution containing benzoic acid, cellulose, and methyl orange involves many components pertaining to the fundamental ideas of solubility and polarity. Using the concepts of like dissolving like and acid base reactions, a solution of organic acid (benzoic acid), a water soluble compound cellulose, and an organic soluble compound methyl orange, can be separated and benzoic acid can be isolated by a method of extraction.

At the fundamental level, organic solvents separate from aqueous solutions based on their varying densities, typically the organic layer being less dense and therefore on top of the aqueous layer1. Therefore any solutes in those solutions are also separated and can be isolated from one another. This phenomenon is the basis for the liquid-liquid extraction and leads into the concept of the partition coefficient. According to MtCg the ratio of concentrations of a solute in each layer is defined by the partition coefficient K, where K = C2 / C1.

The distribution coefficient can therefore be viewed as the ratio of the concentration of the compound in organic solvent to the concentration of the same compound in aqueous solution. This constant allows for the calculation of dissolved compound in each layer of the solution, so that after several extractions, the yield can be sufficient for the purposes of the experiment. A second type of extraction, acid-base extraction, involves the addition of acids and bases in solutions to change the polarity of organic acids and bases to their corresponding water-soluble salts2.

This allows us to take advantage of the liquid-liquid extraction to separate organic acids and bases from solution mixtures. Such extraction can be considered chemically active extraction because the polarity of one substance is altered to increase solubility in water. This type of extraction is necessary when both compounds are non-polar and dissolved well in organic solvents. For Experiment #1 Extraction of Benzoic Acid, a solution of benzoic acid, cellulose and methyl orange will first be added to ether, heated and filtered to separate the organic insoluble cellulose leaving benzoic acid nd methyl orange. Then after adding NaOH, the benzoic acid will react to form the water-soluble salt, sodium benzoate, which can be separated via the liquid extraction technique. Finally adding HCl to the aqueous sodium benzoate will cause the acid-base reaction to undergo restoring benzoic acid in the organic layer and NaCl in the water layer. Reagent Table: Experimental: To start, a solution of diethyl ether was mixed with 4. 06g of crude benzoic acid with two impurities.

Boiling stones were added to the mixture and heated over the steam bath until the ether solution began to boil. Once the solution was boiling to most efficiently dissolve the inorganic parts of the solution, the ether insoluble material was filtered out of solution using the Buchner funnel vacuum filtration technique. The filtrate ether remaining was added to a separatory funnel with 30mL of 1M NaOH, mixed and vented properly, and then rested as the solution settled into separate organic and aqueous layers.

The bottom layer (aqueous) was drained from the separatory funnel into a beaker and another 30mL of NaOH was added to the left over ether, swirled and vented, separated, and the aqueous layer drained off into the same beaker as the first aqueous extraction. Next the aqueous solution that was collected was cooled on ice and 50mL of chilled 6M HCl was added to the mixture. At this point, a Bruchner funnel was used to collect the solid precipitate via vacuum filtration and those collected crystals were weighed out and set aside for the recrystalization of benzoic acid.

Results: The most important measurements made during this lab were the initial weight of the crude benzoic acid, which was 4. 06g, and the mass of the crystals after the separation from the two impurities, 4. 88g. The fact that the crystals weighed more than the starting material can be accounted for based on the lack of proper drying time for the crystals, and will be accounted for when calculating the percent composition.

Discussion: After the results of the lab, there were a few points to consider in the final analysis. First off, and most importantly, after the crystals were obtained from the aqueous solution obtained by adding NaOH, the crystals were used immediately for the recrystalization and were not given the proper time to dry out, so the weight of the wet crystals must be used to calculate the percentage composition, which will be inaccurate.

Another important note was after the HCl was added to the aqueous solution, the solution turned bright pink, indicating that some of the methyl orange, which should have remained in the organic layer in the separatory funnel, had made it into our aqueous solution. To counteract this, when the vacuum filtration technique was used, the solid precipitate was washed with distiller water to ensure the crystals did not contain a pink tint to them.

The reason this lab works was because the first filtration got rid of the organic insoluble cellulose leaving methyl orange and benzoic acid in the ether mixture. Then, using the acid-base extraction technique, benzoic acid was altered to sodium benzoate, rendering it soluble in aqueous solution, which allowed for the separation of the sodium benzoate from the methyl orange (still dissolved in ether) and then the reformation of benzoic acid by adding a strong acid to the aqueous dissolved salt. References: MtCg pg. 129 MtCg pg. 131

Calculate the price
Make an order in advance and get the best price
Pages (550 words)
$0.00
*Price with a welcome 15% discount applied.
Pro tip: If you want to save more money and pay the lowest price, you need to set a more extended deadline.
We know how difficult it is to be a student these days. That's why our prices are one of the most affordable on the market, and there are no hidden fees.

Instead, we offer bonuses, discounts, and free services to make your experience outstanding.
How it works
Receive a 100% original paper that will pass Turnitin from a top essay writing service
step 1
Upload your instructions
Fill out the order form and provide paper details. You can even attach screenshots or add additional instructions later. If something is not clear or missing, the writer will contact you for clarification.
Pro service tips
How to get the most out of your experience with MyhomeworkGeeks
One writer throughout the entire course
If you like the writer, you can hire them again. Just copy & paste their ID on the order form ("Preferred Writer's ID" field). This way, your vocabulary will be uniform, and the writer will be aware of your needs.
The same paper from different writers
You can order essay or any other work from two different writers to choose the best one or give another version to a friend. This can be done through the add-on "Same paper from another writer."
Copy of sources used by the writer
Our college essay writers work with ScienceDirect and other databases. They can send you articles or materials used in PDF or through screenshots. Just tick the "Copy of sources" field on the order form.
Testimonials
See why 20k+ students have chosen us as their sole writing assistance provider
Check out the latest reviews and opinions submitted by real customers worldwide and make an informed decision.
Business and administrative studies
Thank you
Customer 452773, March 19th, 2023
fin571
EXCELLEN T
Customer 452773, March 21st, 2024
Business and administrative studies
excellent job!
Customer 452773, May 25th, 2023
Leadership Studies
excellent job as always
Customer 452773, September 2nd, 2023
Social Work and Human Services
Great work I would love to continue working with this writer thought out the 11 week course.
Customer 452667, May 30th, 2021
Humanities
Thank youuuu
Customer 452729, May 30th, 2021
Human Resources Management (HRM)
excellent job
Customer 452773, July 17th, 2023
Philosophy
Thank you
Customer 452811, February 17th, 2024
Business and administrative studies
Thank you for your hard work and effort. Made a 96 out of 125 points Lacked information from the rubic
Customer 452773, October 27th, 2023
Business and administrative studies
Perfect
Customer 452773, February 23rd, 2023
business
Thank you for your hard work and help.
Customer 452773, February 13th, 2023
Business and administrative studies
perfect
Customer 452773, February 23rd, 2023
11,595
Customer reviews in total
96%
Current satisfaction rate
3 pages
Average paper length
37%
Customers referred by a friend
OUR GIFT TO YOU
15% OFF your first order
Use a coupon FIRST15 and enjoy expert help with any task at the most affordable price.
Claim my 15% OFF Order in Chat
Close

Sometimes it is hard to do all the work on your own

Let us help you get a good grade on your paper. Get professional help and free up your time for more important courses. Let us handle your;

  • Dissertations and Thesis
  • Essays
  • All Assignments

  • Research papers
  • Terms Papers
  • Online Classes
Live ChatWhatsApp