kinetics

Question 1

collision theory

Answer 1

1. molecules must collide together to react
2. When the reactant concentration or temperature will increase, the number of collisions increase, reaction rate increases

Question 2

activation energy (Ea)

Answer 2

1. The minimum energy molecules must possess to react(to break existing bond)s.
2. The source of the energy is heat energy from the surroundings.
3. To get the bonds broken, the activation energy must be reached the transition state.
4. Reactant molecules don’t stay there long and move to the next step of the reaction as the transition state is unstable.

Question 3

Rate of reaction

Answer 3

Rate of reaction is speed at which a chemical reaction occurs.
the change in the concentration of reactants/products per unit of time

• initially the rate of reaction is faster
• factors: temperature, concentration of reactants

Question 4

reaction rate in another word?

Answer 4

the rate of the disappearance of reactants

Question 5

The rate law?

Answer 5

1. Themathematical relationship ofreaction rate with reactant concentrations.

Question 6

the reaction order

Answer 6

The sum of the concentration term exponents in a rate law equation

Question 7

Why m = 0 (concentration term exponents) in zero-order reaction?

Answer 7

Because the rate does not depend on the concentration of reactant in zero-order reaction

Question 8

zero order reaction (rate-concentration of A at a time t-half life-units of rate constant)

Answer 8

rate: k
eq: [A]t = -kt + [A]0
half-life: t1/2 = [A]0/2k
unit of rate constant: moldm-3s-1

Question 9

first order reaction (rate-concentration of A at a time t-half life-units of rate constant)

Answer 9

rate: k[A]1
eq: ln[A]t = -kt + ln[A]0
half-life: t1/2 = ln2/k
unit of rate constant: s-1

Question 10

second order reaction (rate-concentration of A at a time t-half life-units of rate constant)

Answer 10

rate: k[A]2
eq: 1/[A]t = kt + 1/[A]0
half-life: t1/2 = 1/k[A0]
unit of rate constant: mol-1dm3s-1

Question 11

Maxwell-Boltzmann Distribution

Answer 11

1. A graph which shows how the speeds of molecules are distributed for an ideal gas.
2. Ideal gas a hypothetical gas whose molecules occupy negligible space and have no interactions, and which consequently obeys the gas laws exactly.
3. The graph is not symmetrical.

끊임없이 속도 올라가고, 좌편으로는 0 밑으로 내려가지 않음

Question 12

Maxwell-Boltzmann SPEED 종류 및 설명

Answer 12

The most probable speed is located at the peak since it is most likely to be found for a molecule in a gas.

The averagespeedof a molecule in the gas is located a bit to the right of the peak due to the longer “tail” on the right side of the graph. This longer tail pulls the average speed slightly to the right of the peak of the graph.

Question 13

Maxwell-Boltzmann area =

Answer 13

total number of molecules

Question 14

How does a Maxwell-Boltzman distribution of energies diagram change if the number of molecules is decreased?