Stacy runs a paper chromatography experiment using the same ink, but two different solvents.
using solvent a results in the ink separating into three bands, but solvent b does not carry the ink
away from the original spot.
which statement could explain the results?
a. the ink was a pure substance and dissolved in both solvents.
b. solvent a was not a good mobile phase because it could not dissolve the ink.
c. solvent b was not a good mobile phase because it could not dissolve the ink.
d. the ink was a mixture, but only in solvent a.

Option C

Explanation:

Chromatography can be defined as the techniques which can be used to separate the mixture into different components. The mixture is dissolved fluid known as mobile phase.

The solid or liquid phase on which the materials are separated is known as the stationary phase.

If the solvent does not carries the ink from the original point to another point then the solvent B is not a good mobile phase and there is a strong interaction between the stationary and mobile phase.

Hence, the correct answer is option C

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.