BRNBRN

5H21.What number represents the coefficient?

2.What number represents the subscript?

3.What element is represented by the letter “H”?

4.How many “H’s” do you have?

5H21.What number represents the coefficient?

2.What number represents the subscript?

3.What element is represented by the letter “H”?

4.How many “H’s” do you have?

BRNBRN

KNO3 (s) → KNO2 (aq) + O2 (g)

1.What compound(s) are the reactants?

2.What compound(s) are the products?

3.What compound is found in the gas state?

KNO3 (s) → KNO2 (aq) + O2 (g)

1.What compound(s) are the reactants?

2.What compound(s) are the products?

3.What compound is found in the gas state?

Chemical Reactions NotesChemical Reactions Notes

New section in table of contentsNew section in table of contents

Conservation of MassConservation of Mass

Key Concept 1: The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction, it is conserved.

KC 2: The mass of the reactants equals the mass of the products.

massreactants = massproducts

Key Concept 1: The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction, it is conserved.

KC 2: The mass of the reactants equals the mass of the products.

massreactants = massproducts

Chemical ReactionsChemical Reactions

KC 3: The process by which one or more substances are rearranged to form different substances is called a chemical reaction

What are some examples of evidence of a chemical reaction?

KC 3: The process by which one or more substances are rearranged to form different substances is called a chemical reaction

What are some examples of evidence of a chemical reaction?

Representing Chemical ReactionsRepresenting Chemical Reactions

Reactants are the starting substances.

Products are the substances formed in the reaction.

This table summarizes the symbols used in chemical equations.

Reactants are the starting substances.

Products are the substances formed in the reaction.

This table summarizes the symbols used in chemical equations.

Representing Chemical ReactionsRepresenting Chemical Reactions

Key Concept 4: A chemical equation is a statement that uses chemical formulas to show the identities and relative amounts of the substances involved in a chemical reaction.

Key Concept 4: A chemical equation is a statement that uses chemical formulas to show the identities and relative amounts of the substances involved in a chemical reaction.

Balancing Chemical ReactionsBalancing Chemical Reactions

KC 5: Subscripts describe the number of atoms present in one molecule (if it is a molecular compound) or in one formula unit (if it is an ionic compound).

N2 (g) + H2 (g) -------> NH3 (g) 

KC 6: Coefficients are generally used for balancing the chemical equations in accordance with the law of conservation of mass.

N2 (g) + 3 H2 (g) -------> 2 NH3 (g) 

KC 5: Subscripts describe the number of atoms present in one molecule (if it is a molecular compound) or in one formula unit (if it is an ionic compound).

N2 (g) + H2 (g) -------> NH3 (g) 

KC 6: Coefficients are generally used for balancing the chemical equations in accordance with the law of conservation of mass.

N2 (g) + 3 H2 (g) -------> 2 NH3 (g) 

Balancing Chemical ReactionsBalancing Chemical Reactions

Balancing reactions is like a puzzle, you need to make sure both sides of the equation are equal

Helpful Hints: Start with either polyatomic ions or carbon

containing molecules

Never start with balancing oxygen

Write water as HOH (can be easier to see if OH is present on both sides)

Balancing reactions is like a puzzle, you need to make sure both sides of the equation are equal

Helpful Hints: Start with either polyatomic ions or carbon

containing molecules

Never start with balancing oxygen

Write water as HOH (can be easier to see if OH is present on both sides)

Balancing Chemical ReactionsBalancing Chemical Reactions

KC 7: H2 + O2 → H2O KC 7: H2 + O2 → H2O

Balancing Chemical ReactionsBalancing Chemical Reactions

KC 8: Fe + H2O → H2 + Fe2O3 KC 8: Fe + H2O → H2 + Fe2O3

Balancing Chemical ReactionsBalancing Chemical Reactions

KC 9: Dinitrogen pentoxide gas forms nitrogen gas and oxygen gas.

KC 9: Dinitrogen pentoxide gas forms nitrogen gas and oxygen gas.

Types of Chemical ReactionsTypes of Chemical Reactions

KC 10: There are 4 types of chemical reactionsSynthesis

Combustion

Decomposition

replacement

KC 10: There are 4 types of chemical reactionsSynthesis

Combustion

Decomposition

replacement

Don’t forget…Don’t forget…

Some molecules are more stable when they are found as diatomic – two of the same element covalently bonded

Some molecules are more stable when they are found as diatomic – two of the same element covalently bonded

BrINClHOF

BondingBonding

Evidence of a Chemical ReactionEvidence of a Chemical Reaction

KC 11: There are 3 driving forces that are evidence of a chemical reaction: Evolution of a gas

Production of heat

Production of a solid or pure liquid (water)

KC 11: There are 3 driving forces that are evidence of a chemical reaction: Evolution of a gas

Production of heat

Production of a solid or pure liquid (water)

Types of Chemical ReactionsTypes of Chemical Reactions

KC 12: Synthesis – reaction in which 2 or more simpler substances (elements) react to produce a single product (compound) General Reaction : A + B → AB

KC 12: Synthesis – reaction in which 2 or more simpler substances (elements) react to produce a single product (compound) General Reaction : A + B → AB

synthesis synthesis

Types of Chemical ReactionsTypes of Chemical Reactions

KC 13: Combustion – reaction where oxygen combines with a substance (normally contains carbon) and releases energy in the form of heat and lightGeneral Reaction: CxHy + O2 → H2O +

CO2

demo

KC 13: Combustion – reaction where oxygen combines with a substance (normally contains carbon) and releases energy in the form of heat and lightGeneral Reaction: CxHy + O2 → H2O +

CO2

demo

Types of Chemical ReactionsTypes of Chemical Reactions

KC 14: Decomposition – Reaction in which a single compound breaks down into 2 or more elements or new compoundsGeneral Reaction: AB → A + B

demo - 3:00

KC 14: Decomposition – Reaction in which a single compound breaks down into 2 or more elements or new compoundsGeneral Reaction: AB → A + B

demo - 3:00

Types of Chemical ReactionsTypes of Chemical Reactions

1. _______ ___NH3+ ___H2SO4 ___(NH4)2SO4

2. _______ __C5H9O + ___O2 ___CO2 + _H2O

3. _______ ___H2 + ___O2 ___H2O

4. _______ ___NH4OH ___NH3 + ___H2O

5. _______ ___CO + ___O2 ___CO2

1. _______ ___NH3+ ___H2SO4 ___(NH4)2SO4

2. _______ __C5H9O + ___O2 ___CO2 + _H2O

3. _______ ___H2 + ___O2 ___H2O

4. _______ ___NH4OH ___NH3 + ___H2O

5. _______ ___CO + ___O2 ___CO2

KC 15: Correctly identify and balanceeach type of rxnS = synthesis D = decomposition C = combustion

Closure – Exit PassClosure – Exit Pass

1. This type of reaction always forms products of carbon dioxide and water

a. Synthesis

b. Decomposition

c. Combustion

2. What type of reaction has the general format AB → A + B

a. Synthesis

b. Decomposition

c. Combustion

1. This type of reaction always forms products of carbon dioxide and water

a. Synthesis

b. Decomposition

c. Combustion

2. What type of reaction has the general format AB → A + B

a. Synthesis

b. Decomposition

c. Combustion

Types of Chemical ReactionsTypes of Chemical Reactions

KC 16: Single Replacement – Reaction in which the atoms of one element replace the atoms of another element in a compound General Reaction: A + BX → AX + B

Other Information: A metal will not always replace a metal in a compound dissolved in water because of differing reactivities

KC 16: Single Replacement – Reaction in which the atoms of one element replace the atoms of another element in a compound General Reaction: A + BX → AX + B

Other Information: A metal will not always replace a metal in a compound dissolved in water because of differing reactivities

Single Replacement ReactionsSingle Replacement Reactions

Elements will not always replace each other in a single replacement reaction

The activity series tells us if the replacement will occur

Elements replace lower elements in the chart, but not the other way around

Elements will not always replace each other in a single replacement reaction

The activity series tells us if the replacement will occur

Elements replace lower elements in the chart, but not the other way around

Single ReplacementSingle Replacement

Zn(II) (s) + AgNO3 (aq) →

Cl2 (g) + HBr(aq) →

Na(s) + CaO(aq) →

Zn(II) (s) + AgNO3 (aq) →

Cl2 (g) + HBr(aq) →

Na(s) + CaO(aq) →

Fe(III) + PbSO4 →

1. See if the reaction will occur using reactivity series

2. Identify the charges of the elements

3. Do single replacement to predict the products (*same charges switch))

4. Balance the reaction using coefficients

Single Replacement PracticeSingle Replacement Practice

I2 + HCl2 →

Zn(II) + Cu2SO4 →

AlCl3 + Mg →

Cu(I) + Ag2SO4 →

LiNO3 + Ag →

Fe(II) + PbSO4 →

I2 + HCl2 →

Zn(II) + Cu2SO4 →

AlCl3 + Mg →

Cu(I) + Ag2SO4 →

LiNO3 + Ag →

Fe(II) + PbSO4 →

Types of Chemical ReactionsTypes of Chemical Reactions

KC 17: Double Replacement – reaction in which the ions exchange between 2 compounds. All double replacement reactions produce either water, a precipitate, or a gas General Reaction: AX + BY → AY + BX

KC 17: Double Replacement – reaction in which the ions exchange between 2 compounds. All double replacement reactions produce either water, a precipitate, or a gas General Reaction: AX + BY → AY + BX

Types of Chemical ReactionsTypes of Chemical Reactions

KC 18: The solid produced during a chemical reaction is called a precipitate.

Precipitation comes from the clouds – “precipitates out”

KC 18: The solid produced during a chemical reaction is called a precipitate.

Precipitation comes from the clouds – “precipitates out”

KC 19: Write a balanced chemical equation for each double-replacement reactions

BaCl2(aq) + K2CO3 (aq) (a precipitate of barium carbonate is formed)

FeS (s) + HCl (aq) (Hydrogen sulfide gas is formed)

Writing ReactionsWriting Reactions

BaCl2(aq) + K2CO3 (aq)BaCl2(aq) + K2CO3 (aq)

FeS (s) + HCl (aq)FeS (s) + HCl (aq)

Predicting Reactions PracticePredicting Reactions Practice

1.Barium chloride + sodium sulfate →

precipitate of barium sulfate is formed

1.Barium chloride + sodium sulfate →

precipitate of barium sulfate is formed

Predicting PracticePredicting Practice

Silver (I) nitrate + calcium sulfide → precipitate of silver sulfide is formed

Silver (I) nitrate + calcium sulfide → precipitate of silver sulfide is formed

PracticePractice

Potassium carbonate + hydrochloric acid (HCl) → a precipitate of hydrogen carbonate is formed

Potassium carbonate + hydrochloric acid (HCl) → a precipitate of hydrogen carbonate is formed

PracticePractice

Sodium sulfate + barium nitrate → a precipitate of barium sulfate is formed

Sodium sulfate + barium nitrate → a precipitate of barium sulfate is formed

SolubilitySolubility

KC 20: Solubility is the maximum quantity of a substance that may be dissolved in another

Solubility… Depends on temperature

Of most solids increases as temperature increases

Of gases decreases as temperature increases

KC 20: Solubility is the maximum quantity of a substance that may be dissolved in another

Solubility… Depends on temperature

Of most solids increases as temperature increases

Of gases decreases as temperature increases

White Solid

Water + universal indicator

Water (at room

temperature)

HCl Methanol IodineTemp of

solubility in water

Baking Soda

GreenSlightly soluble

Produces gas

Insoluble--------

--50 C

SugarYellow-orange

Soluble ---------- InsolubleTurns blue

20 C

Benzoic Acid

Pink Insoluble ---------- Soluble--------

--100 C

Flour Orange Insoluble ---------- InsolubleTurns blue

insoluble

Sodium Chloride

Orange soluble ----------Slightly soluble

----------

20 C

Soluble and Insoluble SaltsSoluble and Insoluble Salts

KC 21: Ionic compounds that

dissolve in water are soluble salts

do not dissolve in water are insoluble salts

KC 21: Ionic compounds that

dissolve in water are soluble salts

do not dissolve in water are insoluble salts

Using Solubility RulesUsing Solubility Rules

Ba(NO3)2(aq) + Li2SO4(aq) →

What does this actually look like?

Ba(NO3)2(aq) + Li2SO4(aq) →

What does this actually look like?

Equations for Forming SolidsEquations for Forming Solids

A full equation shows the formulas of the compounds.

Pb(NO3) 2(aq) + 2NaCl(aq) PbCl2(s) + 2NaNO3(aq)

An ionic equation shows the ions of the compounds.

Pb2+(aq) + 2NO3−(aq) + 2Na+(aq) + 2Cl−(aq)

PbCl2(s) + 2Na+(aq) + 2NO3−(aq)

A full equation shows the formulas of the compounds.

Pb(NO3) 2(aq) + 2NaCl(aq) PbCl2(s) + 2NaNO3(aq)

An ionic equation shows the ions of the compounds.

Pb2+(aq) + 2NO3−(aq) + 2Na+(aq) + 2Cl−(aq)

PbCl2(s) + 2Na+(aq) + 2NO3−(aq)

Equations for Forming SolidsEquations for Forming Solids

Key Concept 22: A net ionic equation shows only the ions that form a solid or water or gas.

Pb2+(aq) + 2Cl−(aq) → PbCl2(s)

The ions that do not form the solid are called spectator ions

2NO3−(aq) + 2Na+(aq) → 2Na+(aq) + 2NO3

−(aq)

Key Concept 22: A net ionic equation shows only the ions that form a solid or water or gas.

Pb2+(aq) + 2Cl−(aq) → PbCl2(s)

The ions that do not form the solid are called spectator ions

2NO3−(aq) + 2Na+(aq) → 2Na+(aq) + 2NO3

−(aq)

Pb2+(aq) + 2NO3−(aq) + 2Na+(aq) + 2Cl−(aq) → PbCl2(s) + 2Na+(aq) + 2NO3

−

(aq)

Predicting ReactionsPredicting Reactions

KC 23: Write the full and net ionic equation for the following reaction – calcium carbonate + potassium phosphate

KC 23: Write the full and net ionic equation for the following reaction – calcium carbonate + potassium phosphate

Predicting ReactionsPredicting Reactions

KC 24: Write the full and net ionic equation for the reaction when calcium chloride reacts with cobalt (II) sulfate

KC 24: Write the full and net ionic equation for the reaction when calcium chloride reacts with cobalt (II) sulfate

Predicting ReactionsPredicting Reactions

KC 25: Write the full and net ionic equation when lithium sulfide reacts with calcium nitrate

KC 25: Write the full and net ionic equation when lithium sulfide reacts with calcium nitrate

SummarySummary

video video

Closure – Exit PassClosure – Exit Pass

1. What is not always an indication that a chemical reaction has occurred?

a. Evolution of a gas

b. Production of water

c. Color change

d. Production of heat

2. What is the reaction type that follows this general pattern – AX + BY → AY + BX

a. Single replacement

b. Double replacement

1. What is not always an indication that a chemical reaction has occurred?

a. Evolution of a gas

b. Production of water

c. Color change

d. Production of heat

2. What is the reaction type that follows this general pattern – AX + BY → AY + BX

a. Single replacement

b. Double replacement