Lab Report 3- Steam Distillation of Carvone PDF

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3 Lab Report Grading Rubric Steam Distillation NAME: Rachel Totos

COURSE-SECTION: CHEM 233_MW 12pm

Grading Rubric

Conclusion &Data Analysis

Calculation

Experimental Procedure & Reaction Table s

Introduction & Reaction Tables

Performance Element

Excellent

Good

Fair

Poor

5 pts: The introduction begins with a statement of the purpose of the lab undertaken and then presents a though, yet, concise, introduction to the chemical theory behind the lab, including a brief discussion of the mechanisms, analytical techniques, etc, At least one diagram supports the written word.

4 pts: The report begins with a statement of purpose. The introduction may miss some of the relevant chemical theory or diagrams, or have a small amount of theory incorrect, but overall demonstrates proficient knowledge about the background material. Final conclusions and overall findings & adequately presented 3 pts: Minor errors in the format or calculations exist, but all required components are present including diagram, quantities, and stoichiometry. The procedure is original and authentic. Some mistakes are present in calculation of rxn table.

2-3 pts: Report may be missing a statement of purpose. Chemical theory background is minimal, contains substantive errors, or lacks application of the theory to the current lab undertaken. Final conclusions and overall findings may be missing, unclear, or lacking detail.

0-1 pt: The introduction does not connect the principles of the laboratory with the chemical theory. Very small amounts of material are presented, and very little original thought is shown.

2 pts: The experimental procedure contains several errors and/or resembles almost exactly the procedure provided by the text with no thought behind the actual procedure followed. One to two components may be missing. Rxn table is incorrect. 3 -2 pt: Some data spectra, tables, calculations, or equations are missing or grossly incorrect.

1 pt: Two or more required components are missing. The procedure is unclear or mimics the text. The procedure lacks or presents incorrect details such as mols, equiv, conc, etc. Details may be missing.

4 pts: The purpose and conclusions of the lab may or may not be correct, but the author of the report makes gross errors in analyzing the data to arrive at any of these conclusions.

3-1pts: Little to no connections between the data acquired and the conclusions of the lab are presented. Data explained contains little thought and depth.

4 pts: Procedural details are written according to the examples provided with the correct format, including product name and reaction diagram. Math (mols, equivs, etc.) is correct. Procedure is original and authentic, and a diagram of the setup is included. Reaction tables are completed and correct.

5 pts: Calculations/equations are shown and explained.

4 pts: Minor errors exist in titles, table presentation, or the description of acquisition method(s) Calculations are shown but have minor mistakes.

6 pts: The conclusion accurately restates the purpose of the lab and concisely indicates whether the purpose and goals were achieved. The data collected is explained and used to verify and prove the concluded outcome. Insightful explanations are offered for unexpected results/procedures.

5 pts: The author accurately restates the purpose of the lab. Data are used to solidly verify and prove conclusions, but with some minor errors in theory and analysis. Explanations for

0-1 pts: Data section is incomplete. There are little to no spectra, tables, or calculations.

Earned Points

Post-Lab

unexpected results are offered.

0 if conclusion is copied from a different source!

Points are assigned (0-10 pts)

Total Score (30 pts) à

Lab Report 3 Steam Distillation of Carvone Rachel Totos TA: Xuan Duong 25 June 2021

Steam Distillation of Carvone Introduction Steam distillation is utilized for isolating and purifying an immiscible volatile liquid that is not reactive with water, has a high boiling point, and is unstable at the boiling temperature.

Steam distillation is not suitable for substances in which react with water or have a vapor pressure less than 5 torr at 100°C. Also, a substance must be immiscible with water and remain stable (does not decompose) at 100°C. An advantage to steam distillation is the distillation of a liquid at high boiling point temperatures up to 100°C, in which prevents decomposition. The goal of this experiment is to isolate the (S)- enantiomer of carvone and compare polarity (from TLC), Baeyer test, IR spectroscopy, and smell (minty or earthy) to the (R)- enantiomer. Enantiomers are configurational isomers that are nonsuperimposable mirror images of one another (see figure one). They have identical chemical and physical properties in an achiral environment and rotate the plane -polarized light in opposites directions with equal magnitude. In this experiment, a Baeyer test for unsaturation is performed to determine the presence of double bonds. The Baeyer reagent, potassium permanganate ( KMnO4 ), is reactive towards alkenes and will produce a colorless product. If no double bonds are present, the purple reagent color from potassium permanganate, will remain after adding it to the solution. Moreover, any area on the TLC plate that does not contain a compound with a double bond will stain purple, and the area of the plate containing an unsaturated molecule will stain brown (manganese dioxide). The disappearance of the purple color and appearance of the brown color once

KMnO4

is added to the solution containing an alkene illustrates a

positive Baeyer test for unsaturation. On the other hand, a negative test result will have no brown participate, and will retain the purple color from complete oxidation reaction between an alkene and

KMnO4 . See figure three for the

KMnO4 .

IR spectroscopy is also utilized in this experiment in order to determine which substance was isolated based on functional groups and other structural characteristics. For the (S/R)-

enantiomers of carvone, the IR spectra, 1H NMR and 13C NMR are the same. Based on the carvone molecules illustrated in table one below, it is expected that there will be major peaks around 1700-1665cm-1 (strong intensity) to represent the conjugate ketone, 1680-1620cm-1 for the saturated alkene and 1650-1600cm-1 (medium intensity) for the conjugated alkene. Carbon-Hydrogen (C-H) stretches should appear around 2900cm -1 for sp3 hybridized C-H bonds and 3100cm-1 for sp2 hybridized C-H bonds, both with medium intensities. S-(+)-Carvone (Caraway seeds)

R-(-)-Carvone (Spearmint leaves)

C10H14O

C10H14O

150.22 g/mol 231°C Spicy, earthy aroma 0.96 +61° 4

150.22 g/mol 231°C mint 0.96 -61° 4

Structure

Formula Molecular weight Boiling point Smell Density Optical rotation Degrees of Unsaturation (IHD)

Table 1. Few characteristics of the (S)- and (R)- enantiomers of Carvone.

Equations & Reactions Retention Factor:

Rf =

distancetravelled by substance d x = ds distnacetravlled by solvent

Raoult’s Law:

Px =N x∗P °

Dalton’s Law:

Ptot =P °x +P° H

Boiling point (...