Vocabulary To Go in Ch. 7 Notes: Grab a BOOK Reactants Products Chemical Equation Coefficients Chemical Energy Exothermic Reaction Endothermic Reaction Reaction Rate Catalyst

Chemical Reactions Chapter 7

Chemical Reactions Chemical Reaction Evidence of a Chemical Reaction Rearranges atoms into different substances Evidence of a Chemical Reaction Temperature change Production of light Color change Production of gas Creation of a precipitate (solid) end

Chemical Equations Chemical Equations 2 parts: Reactants Products ON the LEFT Products ON the RIGHT The State of Matter is with: (s), (l), (g), (aq) aq- aqueous (dissolved in water) 2 H2(g) + O2(g)  2 H2O(l) Yields/Forms/Produces end

Chemical Equations Box the reactants and underline the products 2 H2 + O2  2 H2O Zn + H2SO4  ZnSO4 + H2 2 HgO  2 Hg + O2 end

Chemical Equations The Law of Conservation of Matter Matter CANNOT be created or destroyed! Every atom at the start, must be at the end! MUST BALANCE CHEMICAL EQUATIONS!!! end

NEVER Change the Subscripts Chemical Equations Steps to balancing chemical equations: Write Equation List Elements Multiply by Coefficients Balance elements in 1 place first NEVER Change the Subscripts end

Chemical Equations Practice ___ N2 + ___ H2  ___ NH3 end

Practice ___ KClO3  ___ KCl + ___ O2

Practice ___ CH4 + ___ O2  ___ CO2 + ___ H2O

Practice ___ P + ___ O2  ___ P2O5 ___ NaCl + ___ F2  ___ NaF + ___ Cl2

Practice

Balancing Polyatomic Ions If there is a polyatomic ion in the chemical equation…COUNT IT AS A WHOLE ONLY IF it has ( ) & is on both sides of the equation FeCl3 + NaOH  Fe(OH)3 + NaCl

Chemical Reactions There are 5 basic chemical reactions: Synthesis Decomposition Single Replacement Double Replacement Combustion end

Chemical Reactions Synthesis A + B  AB ___ Mg + ___O2  ___ MgO 2 or more reactants combine to form 1 product A + B  AB ___ Mg + ___O2  ___ MgO end

Chemical Reactions Decomposition AB  A + B 1 reactant breaks down into 2 or more products AB  A + B ___ H2O2  ___ O2 + ___ H2O end

Chemical Reactions Single Replacement A + BC  AC + B 1 element replaces another element in a compound A + BC  AC + B __ Mg + __ HC2H3O2  __ Mg(C2H3O2)2 + __ H2 ___Br2 + ___ MgI2  ___ MgBr2 + ___ I2 end

___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 Chemical Reactions Double Replacement The reactants switch partners AB + CD  AD + CB Often produces water, a gas , or a solid ___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 end

Chemical Reactions Combustion ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O Combine with oxygen give off heat and light Forms CO2(g) and H2O(l) ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O end

Chemical Reaction Classify the following: 2 H2 + O2  2 H2O Zn + H2SO4  ZnSO4 + H2 2 HgO  2 Hg + O2 AgNO3 + NaCl  AgCl + NaNO3 2 C2H6 + 7 O2  4 CO2 + 6 H2O end

Chemical Reaction Complete #1-8 on “Classifying Chemical Reactions”

To Complete & Turn In Worksheet Balancing & Classifying Reactions COMPLETE ALL!!! #5 on Balancing Equations is a Challenge Problem) Vocabulary & p. 198 #1-7 on Back of Worksheet

Bell Ringer What are the 5 types of chemical equations? What does the law of conservation of matter state? What type of Chemical Reaction are these: Mg + 2HCl  MgCl2 + H2O -BALANCE N2 + H2  2NH3 BALANCE

Quick Review from Yesterday

Chemical Reactions There are 5 basic chemical reactions: Synthesis Decomposition Single Replacement Double Replacement Combustion end

Chemical Reactions Synthesis A + B  AB ___ Mg + ___O2  ___ MgO 2 or more reactants combine to form 1 product A + B  AB ___ Mg + ___O2  ___ MgO end

Chemical Reactions Decomposition AB  A + B 1 reactant breaks down into 2 or more products AB  A + B ___ H2O2  ___ O2 + ___ H2O end

Chemical Reactions Single Replacement A + BC  AC + B 1 element replaces another element in a compound A + BC  AC + B __ Mg + __ HC2H3O2  __ Mg(C2H3O2)2 + __ H2 ___Br2 + ___ MgI2  ___ MgBr2 + ___ I2 end

___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 Chemical Reactions Double Replacement The reactants switch partners AB + CD  AD + CB Often produces water, a gas , or a solid ___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 end

Chemical Reactions Combustion ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O Combine with oxygen give off heat and light Forms CO2(g) and H2O(l) ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O end

Chemical Reaction Classify the following: 2 H2 + O2  2 H2O Zn + H2SO4  ZnSO4 + H2 2 HgO  2 Hg + O2 AgNO3 + NaCl  AgCl + NaNO3 2 C2H6 + 7 O2  4 CO2 + 6 H2O end

Write down the following formulas in your BR notebook DEMO DAY Write down the following formulas in your BR notebook

DEMO #1 A + B  AB ___ Mg + ___O2  ___ MgO 2 or more reactants combine to form 1 product A + B  AB ___ Mg + ___O2  ___ MgO end

DEMO #2 AB  A + B ___ H2O2  ___ O2 + ___ H2O 1 reactant breaks down into 2 or more products AB  A + B ___ H2O2  ___ O2 + ___ H2O end

DEMO # 3 A + BC  AC + B __ Mg + __ HC2H3O2  __ Mg(C2H3O2)2 + __ H2 1 element replaces another element in a compound A + BC  AC + B __ Mg + __ HC2H3O2  __ Mg(C2H3O2)2 + __ H2 ___Br2 + ___ MgI2  ___ MgBr2 + ___ I2 end

___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 DEMO #4 The reactants switch partners AB + CD  AD + CB Often produces water, a gas , or a solid ___ Pb(NO3)2 + ___ KI  ___ PbI2 + ___ KNO3 end

DEMO #5 Combustion ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O Combine with oxygen give off heat and light Forms CO2(g) and H2O(l) ___ C2H5OH + ___ O2  ___ CO2 + ___ H2O end

CHEMICAL REACTION DEMONSTRATIONS & BALANCING THEIR EQUATIONS You are to make your own observations per demonstration and write them down, you are also to make an educated guess as to what type of chemical reaction is taking place.

Bell Ringer : TURN IN BALANCING WORKSHEET 1) What can this symbol stand for in a chemical equation:  Circle the reactants, and underline the products in the following chemical equations: FeO3(s) + CO(g) --> Fe(l) + CO2(g) H2SO4 + Pb(OH) --> Pb(SO4)2 + H2O 2) What do the letters (s), (g), (l) in the first chemical equation stand for? 3) What types of chemical reactions are above? 4) How many types of Reactions are there?

Identify Type of Chemical Reaction and Balance: 1) ___Na3PO4 + ___KOH --> ___NaOH + ___KPO4 Type: _____________________________ 2) ___P4 + ___O2 --> ___P2O5 Type:________________________ 3) ___C3H6O + ___O2 --> ___CO2 + ___H2O 4) ___ NO2 --> ___O2 + ___N2 Type: _______________________ 5) ___AgNO3 + ___Cu --> ___Cu(NO3)2 + ___ Ag

Energy Changes Chemical Energy Exothermic Endothermic Stored in chemical bonds Changed during a chemical reaction Exothermic Give off energy Produces heat/light Endothermic Takes in energy Gets cold end

Energy Changes Exothermic Reaction Gives OFF Energy Produces heat and/or light Instant heating pad, glow sticks Energy written as a PRODUCT AB + CD  AD + CB + energy Na + Cl2  NaCl + 411kJ Energy end

Energy Changes In an exothermic reaction: Reactants HIGHER than Products More energy end

Energy Changes Endothermic Reaction Takes IN Energy Gets colder Instant icepacks Energy written as a REACTANT AB + CD + energy  AD + CB 15000 kJ + 6 CO2 + H2O  C6H12O6 + 6 O2 Energy end

Energy Changes In an endothermic reaction: Reactants LOWER than Products Less energy end

Reaction Rates Reaction Rate Speed that Reactants become Products 5 ways to make reactions go faster: end

Reaction Rates Temperature Surface Area Adding Heat = Move Faster Move Faster = Faster Reaction Surface Area Grind into a powder More Surface Area = Faster Reaction end

Reaction Rates Stirring Concentration Moves things around More Movement = Faster Reaction Concentration More Reactants = Easier to Combine Easier to Combine = Faster Reaction end

Reaction Rates Catalyst Speeds up a reaction without being used Lowers energy needed start the reaction The size of the hill Less Energy Needed = Faster Reaction end