Thin-Layer Chromatography Lab 11/12/14
Beginning Question
To what extent does the polarity of a substance affect the distance it travels during TLC using water as the solvent?
Safety Concerns The substances used during the TLC process could possibly be dangerous, so it would be best to avoid getting them on the hands. If one were to accidentally spill the water used in the process onto the floor, a slipping hazard could occur.
Data
Dye
Solvent Front (cm)
Spot (cm)
R
neutral red (NR)
8.7
2.4
0.28
methylene blue (MB)
8.7
0.2
0.023
malachite green (MG)
8.7
0.8
0.10
basic fuchin (BF)
8.7
5.8
0.67
fluoresin (F)
8.7
6.9
0.79
rhodamine B (RB)
8.7
1.9
0.22
unknown
8.7
1.9 and 2.5
0.22 and 0.29
Sample calculation of R(ratio …show more content…
BF has an R value of 0.67 and F has an R value of 0.79. MB, NR, MG, and RB have low R values because they didn’t travel that far, so they have a low polarity because they are not attracted to water, which is polar. NR has an R value of 0.28, while MB has an R value of 0.023. MG has an R value of 0.10, while RB has an R value of 0.22. All of these values are significantly lower than the R values of F and BF, so MB, NR, MG, and RB are much less polar than F and BF. …show more content…
When performing TLC, the substance with a larger ratio of spot distance to solvent front would have a higher polarity because it sticks to the mobile phase (water, in this lab’s case) longer than a substance with a lower polarity (Chemwiki). In this lab, methylene blue had the lowest ratio, so it has the lowest polarity, while fluoresin has the highest ratio, so it has the highest polarity. Also, a compound will move farther if it is soluble in the solvent (water) than a compound that is not soluble (Chemwiki). Thin Layer Chromatography is a method used in chemistry to determine what a compound is, as well to separate one compound from another (Thin). Polarity is a compound or molecule’s ability to be drawn to or pushed away by other molecules or compounds (Polarity). To study further, the beginning question could be “To what extent does the type of solvent used affect the distance a spot of a substance travels in
Beginning Question
To what extent does the polarity of a substance affect the distance it travels during TLC using water as the solvent?
Safety Concerns The substances used during the TLC process could possibly be dangerous, so it would be best to avoid getting them on the hands. If one were to accidentally spill the water used in the process onto the floor, a slipping hazard could occur.
Data
Dye
Solvent Front (cm)
Spot (cm)
R
neutral red (NR)
8.7
2.4
0.28
methylene blue (MB)
8.7
0.2
0.023
malachite green (MG)
8.7
0.8
0.10
basic fuchin (BF)
8.7
5.8
0.67
fluoresin (F)
8.7
6.9
0.79
rhodamine B (RB)
8.7
1.9
0.22
unknown
8.7
1.9 and 2.5
0.22 and 0.29
Sample calculation of R(ratio …show more content…
BF has an R value of 0.67 and F has an R value of 0.79. MB, NR, MG, and RB have low R values because they didn’t travel that far, so they have a low polarity because they are not attracted to water, which is polar. NR has an R value of 0.28, while MB has an R value of 0.023. MG has an R value of 0.10, while RB has an R value of 0.22. All of these values are significantly lower than the R values of F and BF, so MB, NR, MG, and RB are much less polar than F and BF. …show more content…
When performing TLC, the substance with a larger ratio of spot distance to solvent front would have a higher polarity because it sticks to the mobile phase (water, in this lab’s case) longer than a substance with a lower polarity (Chemwiki). In this lab, methylene blue had the lowest ratio, so it has the lowest polarity, while fluoresin has the highest ratio, so it has the highest polarity. Also, a compound will move farther if it is soluble in the solvent (water) than a compound that is not soluble (Chemwiki). Thin Layer Chromatography is a method used in chemistry to determine what a compound is, as well to separate one compound from another (Thin). Polarity is a compound or molecule’s ability to be drawn to or pushed away by other molecules or compounds (Polarity). To study further, the beginning question could be “To what extent does the type of solvent used affect the distance a spot of a substance travels in