7.1.P9

Consider an gas whose chemical composition is H₅N₃C₇O₇. In an experiment performed in a closed container, this gas is observed to decompose into a mixture (all gases) of carbon monoxide (CO), hydrogen gas (H₂ ), and nitrogen gas N₂ . For the purposes of this problem, consider all the gases to be ideal.

A. Determine the smallest integer stoichiometric coefficients, x, y, z, w, that balance this reaction:

w H₅N₃C₇O₇  →  x CO + y H₂ + z N₂

B. If there are N molecules of the original gas and the reaction proceeds to completion, how many product molecules are produced

C. For each of the following conditions on the reactions, select ”increases, decreases, remains the same, or "cannot be determined with the information given” that makes the statement correct.

C.1 If the reaction takes place at constant temperature and volume, the pressure ___.

C.2 If the reaction takes place at a constant temperature and pressure, the volume ___.

Explain why you chose the answers you did. If you chose ”not enough information”, indicate what you would need to know in order to answer.

D. 

D.1 If the reaction takes place at constant temperature and volume, how much work does the gas perform on the outside world?

D.2 If the reaction takes place at constant temperature and volume, and if the initial pressure is 4 x 10⁵ Pa, without doing a calculation, can you tell the final pressure greater than or less than atmospheric pressure?

D.3 What is the final pressure (in Pa)?

D.4  The experiment is repeated several times, using different containers. Some containers seem to be defective and are observed to fail when this reaction takes place. Assuming the temperature of the reaction does not affect the container, how would you describe why the defective containers might be failing?

Bill Dorland 1/4/19