Objective. SWBAT identify the 5 types of reactions by analyzing the structure of chemical reactions

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1 Science Starter 1. What do we call the ingredients of a chemical reaction? What is produced? 2. What are the indicators of physical change? 3. What are the indicators of chemical change? 4. Why do we have to start and end with the same amount of stuff? (Think: what laws have we talked about?

2 Objective SWBAT identify the 5 types of reactions by analyzing the structure of chemical reactions SWBAT recall and define the indicators of chemical and physical change

3 Agenda Science Starter Announcements Unit 3 Test Tracking & Progress Reports Phys/Chem changes review Types of Chemical Rxns Exit Ticket/Homework

4 Announcements Unit 4 Test will be next Friday (short unit!) Midterm is Tuesday March 22 nd for 3 rd block Midterm is Wednesday March 23 rd for 4 th block

5 Unit 3 Test Block 3 Average 70% Block 4 Average 66% Track your data to see where you mastered

6 Unit 4: Chemical Reactions Physical and Chemical Changes Types of Chemical Reactions March 11, 2016

7 Quick Review Physical Changes During a physical change, matter changes form WITHOUT becoming a new substance You start and end with same substance Examples: cutting, freezing, melting, etc.

8 Molecules in Physical Changes

9 Quick Review Chemical Changes During a chemical change, matter changes and becomes NEW substance Start and end process with different substances Usually irreversible (can t change back) Examples: burning, rusting, milk going sour

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11 Indicators that a chemical reaction has taken place: Change in temperature Evolution of a gas Formation of solid Change in smell Change in color

12 Molecules in Chemical Changes The atoms rearrange to make a NEW substance

13 Chemical Change = Reaction Scientists use chemical reactions to describe these chemical changes! Reactants: starting substances in a reaction, ingredients Products: the substances produced after reaction takes place

14 Example: What are the reactants? What are the products? Zn (s) +AgNO 3(aq) ZnNO 3(aq) + Ag (s)

15 Example: C 6 H 12(s) + 9 O 2(g) 6 CO 2(g) + 6 H 2 O (l)

16 Redox Reactions Redox reactions occur when one (or more) species is being oxidized and the other is reduced Oxidation: when electrons are lost Reduction: when electrons are gained These reactions are all about the movement of electrons (either by sharing or transferring!)

17 Type of Reaction Description General Equation Synthesis Example Decomposition Single Replacement Double Replacement Combustion

18 Type of Reaction Description General Equation Example Synthesis two reactants come together to form one product A + B AB 2 Cu + O 2 2 CuO

19 Type of Reaction Description General Equation Example Synthesis two reactants come together to form one product A + B AB 2 Cu + O 2 2 CuO +

20 Type of Reaction Decomposition Description one reactant breaks apart to form two or more products General Equation Example AB A +B 2 H 2 CO 3 H 2 O + CO 2 NOTE: What is the relationship between synthesis and decomposition reactions?

21 Type of Reaction Decomposition Description one reactant breaks apart to form two or more products General Equation Example AB A +B 2 H 2 CO 3 H 2 O + CO 2 NOTE: What is the relationship between synthesis and decomposition reactions? +

22 Type of Reaction SINGLE Replacement Description General Equation Example one element replaces another in a compound! One element ends up single A + BC AC + B 2 Fe + 3 H 2 O 3 H 2 + Fe 2 O 3

23 Type of Reaction SINGLE Replacement Description General Equation Example one element replaces another in a compound! One element ends up single A + BC AC + B 2 Fe + 3 H 2 O 3 H 2 + Fe 2 O 3 + +

24 Type of Reaction Descriptio n General Equation Example Double Replacement ions trade partners, a precipitate forms AB+CD AD+CB CaCl 2 +2AgNO 3 Ca(NO 3 ) 2 +2AgCl

25 Type of Reaction Description General Equation Example Double Replacement ions trade partners, a precipitate forms AB + CD AD + CB CaCl AgNO 3 Ca(NO 3 ) 2 + 2AgCl (Ca, Ag trade; AgCl precipitates) + +

26 What is the difference between double replacement and single replacement? Ni + 2 HCl H 2 + NiCl 2 Na 2 SO 4 +BaCl 2 2 NaCl + BaSO 4

27 Type of Reaction Combustion Description General Equation Example a hydrocarbon reacts with O 2 to produce CO 2 and H 2 O hydrocarbon + O 2 CO 2 + H 2 O C 3 H 8 + O 2 CO 2 + H 2 O + + CO 2

28 FLASH 1. I am about to put up 10 different equations. 2. You and your team must decide what type of reaction is listed. Once you decide and I prompt FLASH! the card with the appropriate chemical reaction.

29 1) NaOH + KNO 3 --> NaNO 3 + KOH Double Replacement

30 2) CH O 2 --> CO H 2 O Combustion

31 3) 2 Fe + 6 NaBr --> 2 FeBr Na Single Replacement

32 4) CaSO 4 + Mg(OH) 2 --> Ca(OH) 2 + MgSO 4 Double Replacement

33 5) Pb + O 2 --> PbO 2 Synthesis

34 6) Na 2 CO 3 --> Na 2 O + CO 2 Decomposition

35 7) 2Al + 6HCl 2AlCl 3 + 3H 2 Single Replacement

36 8) 3H 2 + N 2 2NH 3 Synthesis

37 9) 2H 2 O O 2 + 2H 2 Decomposition

38 10) CH 3 OH + O 2 CO 2 + H 2 O Combustion

39 Worksheet Fill it out. Fill it out. Fill it out.