Which of the following describes the entropy change of a gas reaction? O A. The change in entropy cannot be predicted in a gas reaction.
B. If there is an increase in the number of gas molecules, then AS< 0.
C. If there is an increase in the number of gas molecules, then AS>0.
D. If there is an increase in the number of gas molecules, then AS = 0.

At a certain temperature the rate of this reaction is first order in hi with a rate constant of : 0.0632s2hig=h2g+i2g suppose a vessel contains hi at a concentration of 1.28m . calculate how long it takes for the concentration of hi to decrease to 17.0% of its initial value. you may assume no other reaction is important. round your answer to 2 significant digits.