chem exam 2

Question 1

properties that depend on the number of solute particles, not their chemical identity

Answer 1

colligative properties

Question 2

the change in the concentrations of reactants or products as a function of time

Answer 2

reaction rate

Question 3

rate =

Answer 3

change of concentration / change in time

Question 4

mol / L * s

Answer 4

0 order

Question 5

mol L -1 s -1

Answer 5

0 order

Question 6

1/s

Answer 6

1st order

Question 7

s -1

Answer 7

1st order

Question 8

L / mol *s

Answer 8

2nd order

Question 9

L mol -1 s -1

Answer 9

2nd order

Question 10

L^2 / mol^2 * s

Answer 10

3rd order

Question 11

L^2 mol -2 s-1

Answer 11

3rd order

Question 12

integrated rate law 1st order rearranged

Answer 12

ln [A]t = -kt + ln [A]0

Question 13

integrated rate law 2nd order rearranged

Answer 13

1/[A]t - 1/[A]0 = kt

Question 14

integrated rate law 1/2 life rearranged

Answer 14

[A]t - [A]0 = -kt

Question 15

collisions that actually lead to product

Answer 15

effective collisions

Question 16

the energy threshold that the colliding molecules must exceed in order to react

Answer 16

activation energy (Ea)

Question 17

when reactant molecules collide with a certain minimum energy, from which they can change to products

Answer 17

activated state

Question 18

specific for each reaction ; related to the structural complexity of the reactants and is the ratio of effectively oriented collisions to all possible collisions

more complex molecular structure of reactant, smaller p value

Answer 18

orientation probability factor (p)

Question 19

aka activated complex, formed by an effective collision between particles ; is an unstable species that contains partial bonds and is a pathway between reactants and products

Answer 19

transition state

Question 20

plots how potential energy changes as the reaction proceeds from reactants to products

Answer 20

reaction energy diagram

Question 21

reaction rate (increases/decreases) exponentially as temperature increases

Answer 21

increases

Question 22

the product of the collision frequency Z and the orientation probability

A=pZ

Answer 22

frequency factor (A)

Question 23

the sequence of single reaction steps that make up an overall equation

Answer 23

reaction mechanism

Question 24

as activation energy increases, reaction speed (increases/decreases)

Answer 24

decreases

Question 25

(T/F) the freezing point depression of a soln depends on both the type and quantity of particles

Answer 25

false, only number of solute particles

Question 26

(T/F) the unit of the rate of reaction depends on the order of the reaction

Answer 26

false, unit has to be mol * L-1 * s-1

Question 27

(T/F) the reaction rate constant k depends on the order of reaction

Answer 27

true

Question 28

(T/F) a transition state is a species (or state) corresponding to an energy maximum on a reaction energy diagram

Answer 28

true

Question 29

(T/F) in a reversible reaction, a catalyst will speed up the fwd reaction, but not affect the rev reaction

Answer 29

true

Question 30

(T/F) a catalyst lowers the energy of activation and alters the mechanism of a reaction

Answer 30

true

Question 31

which order reactions' half-lives DO depend on the initial concentration

Answer 31

zero, second, third

Question 32

which order reactions' half-lives DO NOT depend on the initial concentration

Answer 32

first

Question 33

(T/F) osmotic pressure of a solution depends on its temperature measured in kelvin

Answer 33

true

Question 34

which compounds automatically do not have a van't hoff factor

Answer 34

covalent compounds

Question 35

(T/F) the boiling point elevation of a solution depends on the type of solute particles dissolved in the solvent

Answer 35

false

Question 36

(T/F) the addition of a non-volatile solute to a solvent would result in a decrease in the solvents vapor pressure

Answer 36

true

Question 37

(T/F) the osmotic pressure of a solution is the pressure needed to halt the osmotic flow of solvent into the solution

Answer 37

true

Question 38

order for graph of (ln [A]t)

Answer 38

first order

Question 39

order for graph of (1 / [A]t)

Answer 39

second order

Question 40

order for graph of ([A]t)

Answer 40

zero order