Site Loader
Rock Street, San Francisco

Allowed layers to separate. Upper layer determined to be aqueous by density: lower layer removed. Upper layer placed into separate flask labeled “A” for acid extract. Lower layer placed into seep. Funnel and recreated with 15 ml 3 M HCI. Combined aqueous layers in flask A Recreated CHICHI layer containing chemicals with 15 ml 3 M Noah. Upper layer in flask labeled “B” for base extract. Re-extract organic layer with 15 ml MM Noah. Combined base extracted materials in flask “B”. Saw bubbles during mixing, heard the evolution of gas while venting.

Dried organic layer with Andy. Nassau until free flowing salt was observed (about 3 grams). Filtered the organic solution into a tarred 100 ml round-bottom flask. Rinsed flask and funnel with 10 ml of CHICHI and rotated off remaining solvent and weighed flask. The phenyl obtained was white in color and was like a powder. Weight of flask and phenyl = 106. 1784 g Weight of empty flask 104. 7368 g Weight of recovered phenyl = 1. 4416 Cooled flask A in a water bath. Added 18 ml 6 M Noah and pH tested. Still acidic, litmus paper was red. Added 1. L more 6 M Noah; and the alkaline solution became cloudy and pH paper turned blue. Yellow crystals were seen to form. Cooled in ice bath for 21 minutes. Collected p-international (yellow crystals)using vacuum filtration. Washed with cold water and allowed to dry for 12 minutes Dry solid p-international and watch glass = 18. 9372 g Watch glass = 18. 0512 g Weight of recovered p-international = 0. 8660 g Cooled flask B in an ice water bath. Added 16 ml 6 M HCI and pH tested. Still alkaline, litmus paper is blue. Added 0. 5 ml more 6 M I-IAC till solution became loudly and litmus paper turned red.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

White plate/leaflet like crystals was obtained. Cooled in ice bath for 25 minutes and collected benzene acid using vacuum filtration. Dry solid benzene acid and watch glass = 17. 5631 g = 16. 9512 g Weight of recovered benzene acid = 0. Egg Discussion: In this lab, a mixture of three solids was separated to their individual components by extraction, based upon their acid-base properties. The acid (benzene acid) reacted with Noah to give a salt that moved from the organic phase to aqueous phase and thus was removed from the mixture.

P-International being a base, reacted with HCI to give it’s millennium salt which moved from the organic phase to the aqueous phase. The component remaining in the organic phase was the neutral phenyl. Both the acid and base extracts were neutralized to give benzene acid and p-international as solids. By adding up the weights of the various components without any loss, I should have recovered 3. 2568 g of starting material. Weight of phenyl = 1. Egg Weight of p-international = 0. 8660 g Weight of benzene acid = 0. 6119 g Total solid recovered = 2. 195 g Total recovered mass Mass of starting material = 3. 2568 g Total % recovered 89. 6 % {like wise you all will need to calculate individual % recovery of the three compounds, assuming that 1 g each of the three compounds contained in the original mixture} recovered 89. 6% of my starting material. Because of solubility issues (difficulty dissolving all of the starting material) know that some of the starting material never left the first flask. There was a green film all over the glassware indicating an incomplete transfer.

Post-laboratory Questions 1. Why is it better to extract twice with 15 ml portions of solvent 2 instead of once with a 30 ml volume of solvent 2? Assume K/1 = 4 and start with 10 grams in 100 ml of solvent 1. Will not answer this question for you. You should be able to answer this question by going over the sample handout that I gave you during lecture. 2. Write equations for the acid-base reactions involved in this experiment. Draw out all the detailed acid base reactions that takes place during each of the extraction steps.

Conclusion: The implication of “like dissolves like” has implications in daily life from washing sizes and hair all the way to oil spills in the North Atlantic. In this lab exercise we took advantage of the properties of the materials to move them into and out of various phases by using the acid base properties of the compounds. Benzene acid is soluble in CHICHI until it is depredation and becomes highly water soluble, but neither the acid nor the base changes the solubility of phenyl. This is not surprising since phenyl doesn’t contain the kinds of functional groups that would be affected by adding or removing protons.

Post Author: admin

Leave a Reply

Your email address will not be published. Required fields are marked *

x

Hi!
I'm Eric!

Would you like to get a custom essay? How about receiving a customized one?

Check it out