Passage I

A reaction is at equilibrium when the rate of the forward reaction equals the rate of the reverse reaction. At equilibrium, the ratio of product concentration(s) to reactant concentration(s) is the equilibrium constant, K.

Consider the following reaction at equilibrium:

X + Y Z

For this reaction, K is given by:

The brackets ([ ]) around the symbol for a substance indicate the equilibrium concentration of the substance.

This reaction was studied in 10 trials. Trials 1-5 were conducted at the same temperature (see Table 1 ) , and Trials 6-10 were conducted at different temperatures (see Table 2).

6. Assume that substances X, Y, and Z were gases throughout each trial. The boiling points of X, Y, and Z must each be:

Answer and Explanation

Your Answer is

Correct Answer is F

Explanation

The question says that under all experimental conditions in the article, X, Y, and Z are all gases, indicating that all reaction temperatures are higher than the boiling point of these three substances, so their respective boiling points must be lower than -15 degrees Celsius , otherwise, in the case of -15 degrees, there must be some substances in liquid state instead of gaseous state