Orders and the rate equation 116-117

Question 1

Why does a greater concetration of reactants mean a faster reaction?

Answer 1

The greater the concentration the larger the number of collisions per second.

Question 2

For a reactant A, what is the rate of the reaction proportional to?

Answer 2

rate = K x [A]^x

where K shows proportionality, x = the order with respect to A. A is concentration of reactant A.

Question 3

What is zero order?

Answer 3

If the order is 0 with respect to a reactant A, then rate = k x [A]⁰.

The rate is unaffected by changing the concentration of A.

Question 4

What is first order?

Answer 4

If the order is 1 with respect to a reactant B, then rate = k [B]¹.

• If [B] increases by 2 times, the rate also increases by 2 times.
• If [B] increases by 3 times, the rate also increases by 3 times.

Question 5

What is second order?

Answer 5

If the order is 2 with respect to a reactant C, then rate = k x [C]².

If [C] increases by 2 times, the rate increases by 2² = 4 times.

If [C] increases by 3 times, the rate increases by 3² = 9 times.

Question 6

Define the rate constant.

Answer 6

The rate constant,k, is the constant that links the rate of reaction with the concentrations of the reactants.

Question 7

Give the rate equation.

Answer 7

The rate equation for a reaction A + B → C is given by rate = k[A]^m[B]ⁿ.

m is the order of reaction with respect to A.

n is the order of reaction with respect to B.

Question 8

Define overall order of reaction.

Answer 8

The overall order of reaction is the sum of the individual orders, m + n.

Question 9

How is the rate equation determined?(How do scientists find it out?)

Answer 9

The rate equation can be determined only from experimental results.