Interpretation: The weight and mole percent compositions of the distillation fractions A, B and C need to be determined.
Concept Introduction: The results of the gas chromatography are obtained as peaks on the chromatogram. From these peaks, the relative amount of each of the components of the mixture can be determined. It is assumed that peaks are symmetrical; the area under the peak can be calculated taking it an equilateral triangle. The area under the peak can be calculated as product of the width at half of its height and height of the peak. This varies with compound to compound. The analysis of various functions obtained during fractional distillation of the mixture of toluene and cyclohexane gives GLC traces in figure 6.16. Peak having shorter retention time is for cyclohexane and with larger time is for toluene.
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EBK EXPERIMENTAL ORGANIC CHEMISTRY: A M
- 1. Are there any difference between using a 2% NaCl and using a water in the paper chromatography. If there are, what is the differences between the two? If they are the just the same, state the reasons.arrow_forwardWhich statement about the determination of the percentage purity of benzoic acid is correct? * A- Only sodium hydroxide solution can be used as the titrant in the volumetric analysis of benzoic acid. B- Analysing a benzoic acid sample that still contains some hydrochloric acid may yield an analyte percentage that is less than expected. C- Analysing a wet benzoic acid sample may yield an analyte percentage that is more than expected. D- All these statements are correct. E- None of these statements are correct.arrow_forwardPART1: Put True (T) or False (F) for the following sentences: 1. chromatography" derived from two Greek words "Chroma" meaning color and "graphein" meaning to write. The stationary phase may be a solid, or a liquid supported on a solid or gel. 3. The mobile phase may be 2. Solid. 4. Silica gel is the most common stationary phase in adsorption chromatography. 5. Liquid Chromatography abbreviated as (GC ). 6. In Thin Layer Chromatography, the mobile phase is gas. 7. a = KB/KA, where Kg is the distribution constant. 8. k'B and k'A are the retention factors. 9. Rf, is the distance traveled by the compound ONLY. 10. Chromatography is a physical method of separation.arrow_forward
- A three-component mixture containing compounds A, B, and C is separated by simple distillation. A fraction from that distillation is collected and analyzed by gas chromatography. The resulting chromatogram is overlaid on a ruler in the figure shown below. Using this figure and the data contained therein, determine the percentage composition of each component in this fraction by the triangulation method (i.e. determine the percentages of A, B, and C in this fraction). Be sure to show the setup for your calculations. 15 10 AAA 5. B 10 15 20 25 30 35 (both axes are in mm)arrow_forwardYou are attempting to purify a compound via recrystallization. You prepare the process through the following method: 1) Dissolve the material in a minimal amount of hot EtOH. 2) Slowly add hot water until the compound is slightly cloudy. 3) Add a small amount of EtOH until the solution is just clear (still hot). 4) Cool to RT. Upon cooling to RT you notice that the compound is not precipitating out of solution. You decide to boil off some ethanol. Upon completing this step and cooling to RT you notice that the compound is precipitating out as desired! In which solvent is your compound the least soluble? Ethanol O Water O The ethanol water mixture Insoluble in all of these solventsarrow_forwardi need help determining amount recovered in an extraction. i started with a .51g mix of naphlathene/benzoic acid. then, i ended up with the organic in the flask weighing 56g, with the initial weight of the flask without product being 46g. how do i determine amount recovered AND the % recovery?arrow_forward
- a) What would you see if you ran a Thin Layer Chromatography (TLC) on a mixture of the three solids shown below using silica gel as the stationary phase and ethyl acetate/hexanes as the mobile phase? Whichsolid would have the highest Rf and which would have the lowest Rf? Explain b) Would changing the mobile phase (from part a) and increasing thepolarity by introducing small amount of methanol to the mobile phase change the order ofRf of the above 3 compounds? Explain c) Another type of chromatography is Reverse Phase Chromatography. In this type ofchromatography, the stationary phase is non-polar and the mobile phase is polar. If astudent performed Reverse Phase TLC on the mixture of 3 solids (from part a),what would be the order of Rf’s of the compounds? Which would have the lowest Rf andwhich would have the highest Rf?arrow_forwardPls do fast within 5 minutes and i will give like for sure Solution must be in typed form To plan a liquid–liquid extraction we need to know the solute’s distribution ratio between the two phases. One approach is to carry out the extraction on a solution that contains a known amount of solute. After the extraction, we isolate the organic phase and allow it to evaporate, leaving behind the solute. In one such experiment, 1.235 g of a solute with a molar mass of 117.3 g/mol is dissolved in 10.00 mL of water. After extracting with 5.00 mL of toluene, 0.889 g of the solute is recovered in the organic phase. If we extract 20.00 mL of an aqueous solution that contains the solute using 10.00 mL of toluene, what is the extraction efficiency?arrow_forwardQ1. Give three criteria for a good recrystallization solvent. Q2. You want to purify 10 grams of benzoic acid that has been contaminated with 0.2 g of salicylic acid. You are given the following data: Solubility in water at 20 °C Solubility at 100 °C (g/10 ml) Compound (g/10 ml) Benzoic Acid 0.029 0.680 Salicylic Acid 0.680 0.029 0.22 6.67 a) What volume of Boiling water is needed to dissolve the 10 g of benzoic acid? (show calculations) b) How much benzoic acid will crystallize after cooling to 20 °C (show calculations) c) Will any salicylic acid crystals form? Why or why not? (show calculations/ reason for answer) d) What is the maximum amount of benzoic acid that could be recovered in the first crop of this recrystallization? (Show calculations) e) How can you prove the purity and identity of the purified Benzoic acid?arrow_forward
- 16) Which of the following(s) is/are correct? I- Selectivity factor is the amount of time a solute spends in the stationary phase relative to the time it spends in mobile phase II- The retention time for an analyte is the time interval between its injection onto a column and its appearance at the detector at the other end of the column. III- Distribution constant is the ratio of the total solute concentration in the stationary phase to that in the mobile phase. A) I, II and III B) Only II C) I and III D) II and III E) Only III for GC2arrow_forwardYou are carrying out an experiment by analysing alcoholic drinks by gas chromatography. Why is Gas chromatography the best technique used for this analysis? Why is Carbowax a suitable stationary phase for this analysis? What gases are used and what is their purpose and source?arrow_forwardThe liquid-liquid extraction is the classical technique in chemistry to isolate a target component from a mixture. Organic Solvent is the usual solvent being used along with water. TRUE or FALSEarrow_forward
- EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENT