Consider the following reaction:
3A - 2B
The average rate of appearance of B is given by O[B]/Ot. Comparing the rate of appearance of B and the rate of disappearance of A, we get O[B]/Ot = × (- O[A]/Ot).

Question

Quizplus · Accepted Answer

The balanced chemical equation tells us that for every 3 molecules of A that react, 2 molecules of B are formed. Therefore, the rate of disappearance of A is (-1/3) times the rate of appearance of B. Thus, O[A]/Ot = (-1/3)O[B]/Ot, which can be rearranged to give O[B]/Ot = (-3/1)(-1/3)O[A]/Ot, or O[B]/Ot = (1/3)O[A]/Ot. Simplifying, we get O[B]/Ot = (2/3)(-O[A]/Ot), which gives us the answer D.

Consider the Following Reaction