4.12 Types of chemical reactions

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Types of Chemical Reactions
Unit: 4

Lesson:
12

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Review Question

How many atoms of oxygen are on
each side of this balanced equation?

6CO2 + 6H2O C6H12O6 + 6O2

Elements of

Surprise, Silence,

and Confusion

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Review Question

How many atoms of oxygen are on
each side of this balanced equation?

6CO2 + 6H2O

C6H12O6 + 6O2

6x2 + 6 = 18

6 + 6x2 = 18

Answer

Poll

have you ever used the product ice melt?

• yes

• no

• I'm not sure

Poll

Have you ever used hand warmers?

• yes

• no

• Im not sure

Poll

Have you ever used an ice pack?

• yes

• no

• Im not sure

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Types of Chemical Reactions {Chem Rxn}

Synthesis – combining
Decomposition – breaking down
Combustion – burning
Single Replacement – one exchange
Double Replacement – two exchanges

There are 5 types of chemical reactions:

Lets look at each one in more depth.

Simpler materials combine to make a compound

Synthesis

compound broken down into simpler materials

Decomposition

Compound containing carbon and hydrogen combines with oxygen gas to produce carbon dioxide and water.

Combustion

one element that starts out by itself switches with another element in a compound.

Single replacement

two positive and negative ions in two different compounds switch places

Double replacement

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Practice or Check

Identify the following into types of chemical reactions

Equation

Type of Chem Rxn

Na (s) + Cl2 (g) --> NaCl(s)

Cu(s) + AgNO3 (aq) --> Ag(s) + Cu(NO3)2 (aq)

C3H8(g) + O2 (g) --> CO2 (g) + H2O(g)

CaCO3(s) --> CaO(s) + CO2 (g)

KBr(aq) + AgNO3(aq) --> AgBr (s) + KNO3 (aq)

Match

match the equation to the type of chemical reaction

synthesis

single replacement

combustion

decomposition

double replacement

• synthesis

• single replacement

• combustion

• decomposition

• double replacement

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Endothermic Reaction

An endothermic reaction absorbs heat from the environment

(endo = in).

Ice
(s)

Water

(l)

Vapor

(g)

Heat Enters

melting

evaporating

Heat Enters

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Endothermic Reaction

Sometimes the process of an endothermic chemical reaction
(absorbing heat from the environment) causes the container to

feel cold.

ammonium nitrate and water = cold pack!

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Exothermic Reaction

An exothermic reaction releases heat to the environment (exo =

out).

Vapor

(g)

Water

(l)

Ice
(s)

condensing

freezing

Heat Exits

Heat Exits

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Exothermic Chemical Reaction

Sometimes the process of an exothermic chemical reaction (releasing

heat to the environment) causes the container to feel hot.

magnesium sulfate and water = hot pack!

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Practice or Check

Which of the following are endothermic or exothermic?

Occurrence

Endo or Exo?

Ice Melting

Cooking an Egg

Mixing Baking Soda and Vinegar

Burning Wood for a Fire

Lake Freezing Over

Fireworks

Categorize

Options (6)

ice melting

cooking an egg

mixing bakingsoda and vinegar

burning wood for a fire

fireworks

lake freezing over

Which of the following are endothermic or exothermic?

Endothermic

Exothermic