Class 4

Question 1

Can you detect/isolate an intermediate? And a transition state?

Answer 1

Intermediates CAN be detected/isolated. Transition states CANNOT

Question 2

What is the rate law for the overall process of a multi-step reaction?

Answer 2

The rate law for the rate-limiting step

Question 3

If the concentrations have changed but the reaction rate has not, what can we assume?

Answer 3

The reactant that has changed in concentration and rate has not been affected, must be zero order.

Question 4

If you double the concentration of a subject and the rate doubles, what rate order is this?

Answer 4

1 (first)

Question 5

If the rate changes by MORE than the same factor that the concentration was increased, what rate order is this?

Answer 5

2 (second)

Question 6

Is the rate constant (k) roughly equivalent to the probability of a reaction?

Answer 6

Yes

Question 7

What two things can change the rate constant?

Answer 7

Temperature and catalysts

Question 8

The rate constant is _______ proportional to temperature

Answer 8

directly

Question 9

The rate constant is _________ proportional to activate energy (Ea)

Answer 9

indirectly

Question 10

Is the rate constant affected by the concentration of the reactants?

Answer 10

NO!

Question 11

Do solids or solvents affect equilibrium or rate constants?

Answer 11

No

Question 12

What is the ONLY thing that can change the position of equilibrium, K?

Answer 12

Temperature

Question 13

K = ?

Answer 13

concentration of pdts over concentration of reactants at equilibrium

Question 14

What does it mean when Q = K?

Answer 14

You are in equilibrium; no change

Question 15

What does it mean when Q > K?

Answer 15

Numerator is large; too much product -> will shift toward reactant

Question 16

What does it mean when Q

Answer 16

Denominator is large; too much reactant -> will shift toward product

Question 17

Can heat be treated as either a reactant or a product?

Answer 17

Yes! Depending whether its an endo or exothermic reaction.

Question 18

What happens to all reactions in a system if one reaction shifts?

Answer 18

They ALL shift in the SAME direction

Question 19

How do you combine multiple formation constants?

Answer 19

Multiply, don’t add!

Question 20

What is molar solubility, S?

Answer 20

The maximum molar concentration of a substance that can dissolve

Question 21

What is the common ion effect?

Answer 21

Le Chatliers principle at work. If an ion is added to the solution, the equation will shift to counteract it.