Bell RingerRead the article: “7 things you may

not know about catalysis”

Using the red pens, underline any

words you do not know.

Time Limit: 10 mins

Answer the following questions

1. Name 4 things mentioned in the article that use a catalyst.

2. What is a catalyst and how does it affect a chemical

reaction?

3. Describe the basics of how a lithium-air battery works as

mentioned in the article.

4. What do you already know about catalysts from biology

last year?

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Reaction Rates

Chemical reaction rates depend on factors

that influence the frequency of collision of

reactant molecules.

2

Objective 1Define and describe reaction rate and how it is

affected by different factors.

3

As the reactant amount decreases and product amount

increases in concentration as time progresses.

Reaction Rate

Reactants Productsreactants

products

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2H2 + O2 2H2O

A. an increase in the concentration of O2

and H2 with time

B. an increase in the concentration of

H2O with time

C. an increase in H2 and O2 with time

D. a decrease in H2O with time

Which of these describes the rate of the above

chemical reaction?

5

The rate of a reaction is measured by

calculating change in:

A concentration

B pressure

C temperature

D volume

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Objective 2

Determine qualities and factors that will

change rates of a reaction

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Qualities that change the

reaction rate:

1. Concentration

2. Temperature

3. Pressure

4. Surface Area

5. Catalyst Addition

The more collisions

between the reactants

molecules the faster the

reaction will proceed.

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#1 Concentration

Changes in concentration will change the rate of reaction.

Increase the concentration the reaction will proceed faster.

Decrease the concentration the reaction will proceed slower or stop.

Higher concentration = greater the rate of reaction

High Low

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#2 Temperature

A change in temperature will change the rate of reaction. When you raise the temperature, the frequency of the collisions increases.

INCREASE IN TEMP = INCREASE IN REACTION RATE

DECREASE IN TEMP = DECREASE IN REACTION RATE

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#3 Pressure

Increasing Pressure

Increasing pressure causes more collisions to occur.

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#4 Surface Area

Example: Diced chicken cooks faster than an entire chicken

breast

• The more surface area a reaction has the faster the

reaction will proceed.

• The less surface area a reaction has the slower the

reaction will proceed.

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#5 Catalyst Addition

A catalyst increases

the rate of a reaction

by lowering the

activation energy of a

chemical reaction. It

will then emerges from

the reaction in the

same form as it was

before the reaction.

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A catalyst LOWERS the activation energy.

Activation energy is the energy needed to make

the reaction occur.

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Catalyst Addition

lowers the Activation

Energy of the Reaction

Ea = Activation Energy

Gas molecules X and O react to form new molecules

at standard temperature and pressure (STP). Which

diagram shows where the greatest rate of reaction

will most likely occur?

**Discuss

with

group**

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Higher temperatures will

A. decrease the amount of products in a chemical

reaction.

B. decrease the concentration of products in a

chemical reaction.

C. increase the reaction rate of a chemical reaction.

D. increase the activation energy of a chemical

reaction.

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2H2(g) + O2(g) 2H2O(l)

A Decrease temperature

B Increase volume

C Increase pressure

D Decrease concentration

In the chemical reaction below, hydrogen gas reacts

with oxygen gas to create water. How can the reaction

rate be increased?

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Which of the following would not have an

effect on the rate of a reaction?

A. concentration

B. temperature

C. pressure

D. specific heat

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How does a catalyst affect reaction rates?

A. It decreases the reaction

rate of a chemical reaction.

B. It increases the reaction rate

of a chemical reaction.

C. It shifts the equilibrium

constant of a chemical

reaction to the left.

D. It shifts the equilibrium

constant of a chemical

reaction to the right.

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How does a catalyst usually emerge

from a reaction?

A. In a decrease concentration after

the reaction.

B. As a different molecule than it

was before the reaction.

C. In a different phase than it was

before the reaction.

D. In the same form as it was before

the reaction. No change in form.

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Which potential energy diagram best

shows how a catalyst affects a chemical

reaction?

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Exit Slip

Clear your desk and prepare for the exit

slip.

This activity is to be done completely on

your own.

You are to answer every question!!!

Let’s aim for mastery of these objectives

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#1 This reaction occurs more quickly when

powdered iron is used instead of a single piece of

iron of the same mass because the powdered iron:

A. Acts as a better catalyst than the single piece of

iron

B. Absorbs less energy than the single piece of iron

C. Has a greater surface area than the single piece

of iron

D. Is more metallic than the single piece of iron

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Fe + 2 HCl 1 FeCl2 + 1 H2

#2 If the reaction below takes place inside a sealed

reaction chamber, then which of these procedures

will cause a decrease in the rate of reaction?

A. Adding more CO to the reaction chamber

B. Raising the temperature of the reaction chamber

C. Removing the CO2 as it is formed

D. Increasing the volume inside the reaction

chamber

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2CO + O2 2CO2

#3 Zinc commonly reacts with hydrochloric acid to

produce salt and hydrogen gas. What could you do

to decrease the reaction rate of the chemical

reaction?

A. Heat the mixture to a hotter temperature

B. Use large chunks of zinc instead of powder

C. Increase the pressure on the zinc

D. Increase the concentration of the acid used

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#4 H2O2, hydrogen peroxide, naturally breaks down into

H2O and O2 over time. MnO2, manganese dioxide, can

be used to lower the energy of activation needed for this

reaction to take place and, thus, increase the rate of

reaction.

What type of substance is MnO2?

A. A catalyst

B. An enhancer

C. An inhibitor

D. A reactant

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