Answers to Questions

- Initially two
**A**molecules, represented by red balls, collide and form a**B**molecule represented by a blue ball. After a few seconds some of the**B**molecules that were formed dissociate into**A**molecules. Over the course of the animation a few but not all collisions between two**A**molecules continue to result in the formation of**B**molecules. At the same time some but not all of the**B**molecules continue to dissociate into**A**molecules. After the first fifteen seconds , the number of**A**molecules and the number of**B**molecules appear to remain nearly constant. - Initially, there are 80
**A**molecules (red balls) and zero**B**molecules (blue balls) in the container. The number of**A**molecules rapidly decreases and number of**B**molecules increases. After about 30 seconds the number of**A**molecules and the number of**B**molecules oscillate around the mean values of 28 and 25.

- Initially, there are 40
**B**molecules (blue balls) and zero**A**molecules (red balls) in the container. The number of**B**molecules decreases and number of**A**molecules rapidly increases. Like exercise #2 the number of**A**molecules and the number of**B**molecules oscillate around the mean values of 28 and 25 after about 30 second. The value for the average K_{c}(0.33) is similar the value (0.31) found in exercise #2.

- Both equilibria have the same mean number of
**A**molecules and the same mean number of**B**molecules. The two values for the average K_{c}are similar. The equilibrium states in exercises #2 and #3 are effectively the same state. - At 380
**K**the mean number of**A**molecules (50) at equilibrium is larger than at 298**K**and the mean number of**B**molecules (14) is smaller. The value of average K_{c}is a smaller number (0.054) at 380**K**than at 298**K**. An increase in the temperature causes the equilibrium to shift to the left.