5.1-5.3 Quiz

Question 1

How does volume affect the rate of a reaction?

Answer 1

A decreased volume causes the particles to be closer together which increases the likelihood of effective collisions and increases the reaction rate

Question 2

Reduced

Answer 2

Gain of electrons, number gets lower

Question 3

What is the “k” value in rate law dependent on?

Answer 3

It is dependent on temperature and is different for each reaction and set of conditions

Question 4

What does [A]0 mean?

Answer 4

Initial concentration

Question 5

How do you solve for rate of reaction?

Answer 5

Use the mole ratio

Question 6

How does reactant temperature affect the rate of a reaction?

Answer 6

Higher temperature means the particles are more likely to collide with energy greater than the activation energy

Question 7

What things must happen for a reaction to take place AKA collision theory?

Answer 7

Particles must
- Collide
- With the right orientation
- With energy greater than the activation energy

Question 8

How do you solve for rate of (dis)appearance?

Answer 8

Disappearance will be negative
Appearance will be positive

You need to use the mole ratio from the balanced equation

Question 9

Catalyst

Answer 9

They increase reaction rates without being used up and they decrease the energy needed

Question 10

Why would a rate be negative?

Answer 10

This would be because the amount is decreasing or being used up

Question 11

How do heterogenous catalysts speed up reactions?

Answer 11

They are different phases than the reactants. They alter the orientation of the molecules for more effective collisions

Question 12

What do the half-lives for a first order reaction do?

Answer 12

They remain constant

Question 13

What are the k units for an 1 order problem

Answer 13

1/ time

Question 14

What are the k units for an “n” order problem

Answer 14

1/ M(n-1) time

Question 15

What do the half-lives for a second order reaction do?

Answer 15

They increase

Question 16

When solving for the “k” value and there is a coefficient in front of the product what should you do?

Answer 16

Include that factor in your rate. Ex: If there is a 2 in front of your product, cut the rate provided to you in half, and then solve for k normally.

Question 17

What do the half-lives for a zero order reaction do?

Answer 17

They decrease

Question 18

What determines the overall reaction order?

Answer 18

The sum of the exponents

Question 19

Which equation is used for second order(on equation sheet, just be able to point it out)?

Answer 19

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

Question 20

How do you create rate law with three reactants and experimental data?

Answer 20

Make sure two out of three reactants are constant when trying to determine order

Question 21

How does reactant surface area affect the rate of a reaction?

Answer 21

More surface area increases the chance of the particles colliding; note: something chopped into fine pieces rather than big blocks of something is more surface area

Question 22

How do homogenous catalysts speed up reactions?

Answer 22

They are catalysts in the same phase as the reactants. They provide an alternate pathway to complete the reaction and it takes less activation energy

Question 23

What does half-life tell us about the k value?

Answer 23

The shorter the half-life, the higher the value of k is

Question 24

Which equation is used for zero order(on equation sheet, just be able to point it out)?

Answer 24

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

Question 25

If you are asked about the rate of reaction and feel like you don't have any information about it, where do you look?

Answer 25

Look at reactants with no coefficients or in first order in the rate law because they are directly proportional to the rate

Question 26

Average Reaction Rate formula

Answer 26

Final- Initial Concentration/ Final- Initial Time

Question 27

How do you solve for k in a second-order equation with just data?

Answer 27

Use the equation on the equation sheet. Then, when you get to ln(x)= numbers, do e^numbers= x

Question 28

What does [A]t mean?

Answer 28

Concentration at a specific time

Question 29

How does reactant concentration affect the rate of a reaction?

Answer 29

The higher concentration increases the chance of a collision because more molecules equals more collisions

Question 30

Oxidized

Answer 30

Loss of electrons, number gets higher

Question 31

What do you need to remember about the rate of reaction?

Answer 31

The rate of reaction is always going to be positive

Question 32

Which equation is used for first order(on equation sheet, just be able to point it out)?

Answer 32

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

Question 33

When you are writing a rate of reaction equation what will your A and B values always be?

Answer 33

Reactants

Question 34

When shown multiple graphs and asked to pick the right one what should it look like?

Answer 34

It will be linear, so just look at the y axis to determine what order it is. Second order will always have a positive slope.

Question 35

What are the k units for a 0 order problem?

Answer 35

M/ time

Question 36

How to determine the orders when more than one variable changes?

Answer 36

Experiment blank= Rate2= k2 times [A][B]/ Experiment blank= Rate1= k1 times [A][B]

Question 37

When looking at graphs and trying to determine the order, how do you determine the correct one?

Answer 37

Zero order will be linear. First order will have a constant half-life. Second order will not be linear or have a constant half-life.

Question 38

What is the slope of a 2nd order equation?

Answer 38

k

Question 39

How do you solve a half-life equation that is first order?

Answer 39

First solve for k. Then plug it in the equation on the equation sheet.

Question 40

What is the slope of a 0 and 1 order equation?

Answer 40

-k

Question 41

What are they looking for when asking for half life from a graph?

Answer 41

An amount of time; If every 8 days the amount cuts in half, the half life is 8 days.

Question 42

What type of equation is always first order?

Answer 42

Nuclear or radioactive decay

Question 43

How do you solve for the "k" value when you have a rate law but no rate of reaction?

Answer 43

If the equation is first order use the half-life equation available on the equation sheet. Then use the half-life (_ days/hours/sec, etc.) available.