rates

Question 1

What is the Reaction Rate?

Answer 1

The measure of the change in concentration of the reactants or products per unit time.

Question 2

How is the speed of a chemical reaction defined?

Answer 2

As the change in concentration of a substance divided by the time interval during which this change is observed.

Question 3

Fill in the blank: The formula for rate is _______.

Answer 3

rate=ΔconcentrationΔtime

Question 4

For the reaction A+B→C, how can the rate be expressed?

Answer 4

rate=−Δ[A]Δt, rate=−Δ[B]Δt, rate=Δ[C]Δt

Question 5

What does Δ[A] represent?

Answer 5

The difference between the concentration of A over the time interval t2–t1.

Question 6

Fill in the blank: Δ[A] = _______.

Answer 6

[A]2–[A]1

Question 7

Why are the rates expressed in terms of reactant concentration always preceded by a minus sign?

Answer 7

Because the concentration of a reactant always decreases with time.

Question 8

For the reaction A+3B→2D, how is the rate expressed to avoid ambiguity?

Answer 8

rate=−Δ[A]Δt=−Δ[B]3Δt=Δ[D]2Δt

Question 9

True or False: The concentration of B decreases three times as rapidly as A in the reaction A+3B→2D.

Answer 9

True