Question

Assume you find four bottles in an empty laboratory, each containing a liquid. The labels that were on these bottles have fallen off and are strewn about the bench top. Therefore, you know the contents of the four bottles, but do not know which bottle belonged to which compound. The names on the labels are given below:
trans-1,2-dichloroethylene,
cis-1,2-dichloroethylene,
cyclooctane,
and acetic acid.

Without determining the boiling point, would you be able to identify the contents of each bottle using solubility and polarity (with H2O) information? Explain your reasoning.

Answer 1

Answer:

No, I can not identify the contents of each bottle using solubility and polarity (with H2O) information

Explanation:

While it is true that polar substances dissolve in water and nonpolar substances do not dissolve in water, the task here is to specifically identify the contents of each of the bottles.

Solubility in water can not tell us exactly what liquid is which substance. For instance, trans-1,2-dichloroethylene, cis-1,2-dichloroethylene and cyclooctane are all insoluble in water. The fact that they do not dissolve in water does not tell us which liquid is which compound.

Even though acetic acid is miscible with water, it is not a conclusive prove that the liquid is acetic acid since other polar organic compounds are also miscible in water.

It is only by determining the boiling point of each substance that I can conclusively identify the contents of each bottle since boiling point is an intrinsic property of substances.