Homework Answers
Add Answer to:
1. Why should any marks on the TLC y marks on the TLC plate be done...
2. What are the phases involved in TLC? 3. What is coated on the TLC plate?...
2. What are the phases involved in TLC? 3. What is coated on the TLC plate? 4. What is the purpose of lining the wall of the TLC chamber with paper? 5. Why is it important to use a small amount of the mobile phase? 6. Why should you remove the TLC plate before the mobile phase reaches the top? 7. What type of compounds are visible with UV light? 8. With a polar stationary phase and non-polar mobile phase,...
3. If the TLC plate development had stopped before the solvent front reached the top of...
3. If the TLC plate development had stopped before the solvent front reached the top of the TLC plate (i.e. maybe it reached the middle of the TLC plate when it was stopped, instead): a) Would the Rf values have been affected? If so, how? If not, why not? Give a numerical example to support your answer. b) Would the size of the spots have been affected? If so, how? If not, why not? (Hint: think about the diffusion of...
Consider the following errors that could be made when running TLC. Indicate what should be done...
Consider the following errors that could be made when running TLC. Indicate what should be done to correct the error. A two-component mixture containing 1-octene and 1, 4-dimethylbenzene gave only one spot with an Rf value of 0.95. The solvent used was acetone. A two-component mixture containing a dicarboxylic acid and tricarboxylic acid gave only one spot with an Rf value of 0.05. The solvent used was hexane. When a TLC plate was developed, the solvent front ran off the...
1. What is the purpose of Thin-Layer Chromatography (TLC)? 2. What are the phases involved in...
1. What is the purpose of Thin-Layer Chromatography (TLC)? 2. What are the phases involved in TLC? 3. What is coated on the TLC plate? 4. What is the purpose of lining the wall of the TLC chamber with paper? 5. Why is it important to use a small amount of the mobile phase? 6. Why should you remove the TLC plate before the mobile phase reaches the top? 7. What type of compounds are visible with UV light? 8....
11. Why should you use pencil instead of pen when marking on a thin layer chromatography...
11. Why should you use pencil instead of pen when marking on a thin layer chromatography plate? a. Pencil lead isn't as dark. b. The components of pen ink will separate along with your sample, while pencil lead will not. c. Pen ink will not mark on a TLC plate. d. Pen ink will undergo a chemical reaction with the solvent. 12. Which of the following is not a reason to use thin-layer chromatography? a. To determine the number of...
For TLC plate separation, why do we use Rf values instead of distance measurements (e.g. the...
For TLC plate separation, why do we use Rf values instead of distance measurements (e.g. the spot travelled 5 cm from the starting line)? What would happen if we compared solvent systems using distances rather than Rf values?
Pre-Lab Assignment 1 (detach and submit to your TA at the beginning of your lab session)...
Pre-Lab Assignment 1 (detach and submit to your TA at the beginning of your lab session) Name: Date: 2009.2019 TA: Given the structures of benzophenone and biphenyl (shown below), answer the following questions. blphenyi benzophenone 1. Which of the two structures is more polar and explain why? 2. Which structure would be expected to have a higher R value on a polar TLC plate (ex: silica, alumina) and why? 3. Why is it recommended to spot the analyte on the...
1. A TLC experiment is performed to separate a mixture of the compounds shown below. 5.2...
1. A TLC experiment is performed to separate a mixture of the compounds shown below. 5.2 cm 4.8 cm • C 0-H O-H 2.3 cm • B OCH3 Phenol Cyclohexadiene m-anisic acid 1.1 cm • A a) Draw dipole arrows / dipole moments present for each molecule (if they have any) (2 points) b) The experiment yielded the TLC plate given on the left. Match each spot to one of the three molecules. For each compound, explain what makes it...
Possible Quiz Questions 1 What two methods of visualizing spots on a TLC plate will you...
Possible Quiz Questions 1 What two methods of visualizing spots on a TLC plate will you use in this Give two reasons why would you predict that the elution solvents (hexanes or acetate) would not be visible under UV visualization? week's lab? ethyl 2. Define R 3. Calculate the R of the spot on the following TLC plate. 4. Which compound in each pair is predicted to have the higher Ri? a. CH3CH2CH2CH2OH and CH3CH2CH2CH28r b. CH3CH2CH2CH2OH and CH3CH2CH2CH2CH2CH2CH3 c....
I need help with my pre and post lab questions. The three compounds below were spotted...
I need help with my pre and post lab questions.
The three compounds below were spotted on a TLC plate and developed to give the TLC plate shown. Which compound corresponds to which spot? Calculate the Rf value for spot B in the TLC plate shown above. When using polarity to determine the relative rates at which organic compounds travel up the TLC plate, we are considering compounds of similar molecular weight. It should also be noted that Rf values...
2. What are the phases involved in TLC? 3. What is coated on the TLC plate? 4. What is the purpose of lining the wall of the TLC chamber with paper? 5. Why is it important to use a small amount of the mobile phase? 6. Why should you remove the TLC plate before the mobile phase reaches the top? 7. What type of compounds are visible with UV light? 8. With a polar stationary phase and non-polar mobile phase,...
Consider the following errors that could be made when running TLC. Indicate what should be done to correct the error. A two-component mixture containing 1-octene and 1, 4-dimethylbenzene gave only one spot with an Rf value of 0.95. The solvent used was acetone. A two-component mixture containing a dicarboxylic acid and tricarboxylic acid gave only one spot with an Rf value of 0.05. The solvent used was hexane. When a TLC plate was developed, the solvent front ran off the...
1. What is the purpose of Thin-Layer Chromatography (TLC)? 2. What are the phases involved in TLC? 3. What is coated on the TLC plate? 4. What is the purpose of lining the wall of the TLC chamber with paper? 5. Why is it important to use a small amount of the mobile phase? 6. Why should you remove the TLC plate before the mobile phase reaches the top? 7. What type of compounds are visible with UV light? 8....
Pre-Lab Assignment 1 (detach and submit to your TA at the beginning of your lab session) Name: Date: 2009.2019 TA: Given the structures of benzophenone and biphenyl (shown below), answer the following questions. blphenyi benzophenone 1. Which of the two structures is more polar and explain why? 2. Which structure would be expected to have a higher R value on a polar TLC plate (ex: silica, alumina) and why? 3. Why is it recommended to spot the analyte on the...
1. A TLC experiment is performed to separate a mixture of the compounds shown below. 5.2 cm 4.8 cm • C 0-H O-H 2.3 cm • B OCH3 Phenol Cyclohexadiene m-anisic acid 1.1 cm • A a) Draw dipole arrows / dipole moments present for each molecule (if they have any) (2 points) b) The experiment yielded the TLC plate given on the left. Match each spot to one of the three molecules. For each compound, explain what makes it...
Possible Quiz Questions 1 What two methods of visualizing spots on a TLC plate will you use in this Give two reasons why would you predict that the elution solvents (hexanes or acetate) would not be visible under UV visualization? week's lab? ethyl 2. Define R 3. Calculate the R of the spot on the following TLC plate. 4. Which compound in each pair is predicted to have the higher Ri? a. CH3CH2CH2CH2OH and CH3CH2CH2CH28r b. CH3CH2CH2CH2OH and CH3CH2CH2CH2CH2CH2CH3 c....
I need help with my pre and post lab questions.
The three compounds below were spotted on a TLC plate and developed to give the TLC plate shown. Which compound corresponds to which spot? Calculate the Rf value for spot B in the TLC plate shown above. When using polarity to determine the relative rates at which organic compounds travel up the TLC plate, we are considering compounds of similar molecular weight. It should also be noted that Rf values...
Most questions answered within 3 hours.
-
A college student is employed as a door-to-door newspaper
salesman. Historical data suggests that the student...
asked 2 minutes ago -
Considering gravitational time dilation, calculate the time that
passes in Earth’s surface while 1 hour passes...
asked 26 minutes ago -
Minitab Problem: Take the Lake Hume June rainfall data and find
use the processes outlined in...
asked 1 hour ago -
X Company is trying to decide whether to continue using old
equipment to make Product A...
asked 1 hour ago -
IN PYTHON ONLY !! Program 2: Re-work
program #5 (WeeklyHours) from the previous assignment such that...
asked 1 hour ago -
The average length of time between arrivals at a turnpike
toll-booth is 26 seconds. What is...
asked 3 hours ago -
(a) A piston at 6.1 atm contains a gas that occupies a volume of
3.5 L....
asked 4 hours ago -
Please answer true or false. Words
cannot be changed or added in to make it true...
asked 4 hours ago -
An empty test tube weighs 15.923 grams. Then,
MgCl2•6H2O is added into the test tube. After...
asked 4 hours ago -
Assume memory access is 10 units of time and disk access is
10000 units of time....
asked 5 hours ago -
1. Are all good samples random?
2. Magazines often report surveys giving statistics such as “63%...
asked 5 hours ago -
Under all the various types of market structures, firms
must eventually earn some economic profits for...
asked 5 hours ago