1) Answer either Gravity or Vacuum. What is the most suitable filtering technique for:

A) hot filtration

B) removing decolorizing carbon

C) isolating recrystalized solute from solution

2) What amount, in grams solute per 100 mL solvent, classifies a solute as being "soluble" in a particular solvent?

3) What is the process of seeding, as it applies to recrystalization? What purpose does it serve?

answer

watching

107

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

Sixta KovacekLv2

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

A. The solubitlity of an unkown compound X in ethanol is found to be 0.21 grams per 10mL at 0*C and 1.4 grams per 10mL at 78*C. What is the minimum amount of ethanol needed to recrystallize a 2.0 gram sample of compound X? After recrystallization of the 2.0 gram sample, how much compound X will remain dissolved in the cold solvent (i.e., how much of compound X is not recovered after the recrystallization)?B. Why is it important to use only the minimal amount of hot solvent needed to achieve a recrystallization? What would be the effect using too much solvent while dissolving a solid for recrystalization?C. What do you think would happen to your recrystallization solution if you did not use a preheated filter during the "hot" gravity filtration step?D. Benzyl alcohol has a boiling point of 205*C. It has solubility characteristics that would seem to make it a good choice for use as a recrystallization solvent for fluorenol (m.p. 153-155*C), but in fact benzyl alcohol is a poor choice of solvent for this recrystallization. Why do you think this is? (Hint: you do not need any other information to answer this question.)E. Explain how each of the following contaminants is removed during the recrystallization process:1. sand (inorganic contaminant)2. colored organic contaminants3. a very soluble contaminant

This is the description from my organic chemistry lab.

Lab Observations and Data

We obtained 1.17g of cyclohexene oxide (clear liquid) and 3 mL of water into a 50 mL flask with a stir bar. When added a single drop of sulfuric acid, the clear liquid started to change to a very, very light yellow/brownish color. We obtained an ice bath on the side in case our mixture started to boil. After the solution stirred for about 25 minutes, we added sodium hydroxide. We inserted a pH paper and it turned a dark blue, meaning basic. Added another drop of sulfuric acid to make it a little less basic. Added the mixture to a separation funnel, shook it around and ended with separated layers. We separated the layers, thinking the bottom layer was the organic layer, when it was really the aqueous layer. So we ended up mixing the wrong layers back together. After some error, we isolated our new organic layer and added some drying agent. We then put that mixture with the drying agent, NaOH, into the rotovap. Our final product was a white powder and weighed 1.51 grams. We then set up a vacuum filtration while boiling water. We boiled our dried organic layer into the hexane. Added two drops of ethyl acetate to help the boiling process go faster. After vacuum filtering it, it weighed .394 grams. The melting point is 91 to 93 degrees Celsius. Our IR spectra matches the "trans" conformation. So for our TLC plate we observed blue dots to match the trans conformation.

The question is "calculate your percent yield" Which is actual yield/theoretical yield x 100. I just dont understand how I get those numbers.

Here is the lab manual description as well.

Procedure for the Preparation of 1,2-Cyclohexanediol Place a mixture of 1.18 g (0.012 mole) of cyclohexene oxide and 3 mL water into a 50 mL Erlenmeyer flask, equipped with a magnetic stir bar. To this mixture with vigorous stirring add one drop of 6 M sulfuric acid (33% H2SO4) Caution: After a short incubation time, the reaction mixture will become quite warm. This epoxide ring opening reaction is very exothermic. (Why?) If the reaction mixture begins to boil, place the flask in a bath of ice and water. Allow the reaction mixture to stir for the next 15 minutes and let it cool to room temperature. Afterwards, add a small amount of 10% sodium hydroxide drop-wise to neutralize the stirring solution. (No more than 3 or 4 drops of 10% NaOH should be necessary.) Place a drop of the reaction mixture on pH paper to check the pH. Extract the product from the reaction mixture into ethyl acetate or diethyl ether (2 x 15 mL). Dry the combined extracts over sodium sulfate. Decant the solution and remove the solvent to yield the crude product (~1 g). The product can be purified by recrystallization from a small amount (~ 5 mL) of hot toluene or hexanes. Collection of the purified product by suction filtration yields 1,2-cyclohexanediol. The cis isomer has a melting point of 97-101 Â°C whereas the trans isomer melts at 101-103 Â°C. Determine the product(s) or products the reaction. Include a percent yield calculation in your report along with the results of your TLC analysis

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