Choose the one answer that best answers the question.
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1 | |
Column chromatography separates molecules according to their ___. |
| | A) | molecular size |
| | B) | polarity |
| | C) | solubility |
| | D) | matrix |
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2 | |
In column chromatography, molecules that are ___ move around the beads in the matrix and therefore move through the column ____. |
| | A) | small, quickly |
| | B) | polar, quickly |
| | C) | large, slowly |
| | D) | large, quickly |
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3 | |
In column chromatography, why is the buffer important? |
| | A) | It is the membrane that supports the matrix is the column. |
| | B) | It is the material that fractionates the chemicals in the sample. |
| | C) | It controls the pH of the sample so the shapes of the molecules won't change. |
| | D) | It conducts the electric charge. |
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4 | |
Paper chromatography separates molecules according to their ___. |
| | A) | molecular size |
| | B) | polarity |
| | C) | solubility |
| | D) | matrix |
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5 | |
What is the maximum Rf value for any molecule in paper chromatography? |
| | A) | 0.1 |
| | B) | 1.0 |
| | C) | 10.0 |
| | D) | infinity |
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6 | |
Using paper chromatography, the Rf value for xanthophyll was 0.3 and the value for chlorophyll a was 0.7. What is true for these two pigments? |
| | A) | Xanthophyll is more soluble than chlorophyll a. |
| | B) | Chlorophyll a is a larger molecule than xanthophyll. |
| | C) | Chlorophyll a traveled farther up the paper than xanthophyll. |
| | D) | Chlorophyll a is more polar than xanthophyll. |
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7 | |
Gel electrophoresis separates molecules according to their ___. |
| | A) | wavelengths of light absorbed |
| | B) | polarity |
| | C) | solubility |
| | D) | matrix |
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8 | |
In gel electrophoresis, why is the buffer important? |
| | A) | It is the membrane that supports the matrix is the column. |
| | B) | It is the material that fractionates the chemicals in the sample. |
| | C) | It is the solvent in which the samples are dissolved. |
| | D) | It conducts the electric charge and controls the pH. |
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9 | |
In gel electrophoresis, molecules with a negative charge will ____. |
| | A) | move towards the anode |
| | B) | move towards the cathode |
| | C) | move towards the negative electrode |
| | D) | stay in the well |
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10 | |
If the voltage of the power supply in gel electrophoresis is reduced, how will this affect the results? |
| | A) | The pH will drop and destroy the samples. |
| | B) | The molecules will move slower. |
| | C) | The molecules will move faster. |
| | D) | The voltage of the power supply has no real effect on gel electrophoresis. |
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2002 McGraw-Hill Higher Education