Consider the following hypothetical reaction mechanism A + 3B → 2C. The rate of appearance of C given by d[C]/dt may also be expressed as: A) d[C]/dt = d[A]/dt B) d[C]/dt = −(3/2) d[B]/dt C) d[C]/dt = −(2/3) d[B]/dt E) d[C]/dt = (2/3) d[B]/dt
Solution: Let's write the rate expression
Rate = -Δ[A] = -1 Δ[B] = 1 Δ[C]
Δt 3 Δt 2 Δt
The rate of appearance of C is Δ[C]/Δt. Let's solve for it in terms of B.
-1 Δ[B] = 1 Δ[C]
3 Δt 2 Δt
Δ[C]/Δt = -2/3 Δ[B]/Δt Choice C