When c is increasing at a rate of 1.5*10?2 m? s?1, how fast is b decreasing?

The reaction is:

A (g) + 1/2 B (g) → C (g)

We will rewrite it so the coefficient in the front of C is 1:

1/2 A + 1/4 B → C

So the rate of increasing of C is 4 times faster than the decrease of B.

The rate of B:

- 1.5 · 10^ (-2) M/s : 4 = - 0.375 · 10^ (-2) M/s = - 3.75 · 10 ^ (-3) M/s

Answer: - 3.75 ·10^ (-3) M/s