Chemical Reactions and Reaction Types

1. 2Al + 3Br2 2AlBr3

2. Standard: Identify the reactants, products, and types of different chemical reactions: composition, decomposition, double replacement, single replacement, combustion. Objective: Classify a chemical reaction as composition, decomposition, single replacement, double replacement, and combustion.

3. Chemical Reactions

4. Types of Reactions • There are five types of chemical reactions we will talk about: • Composition reactions (synthesis) • Decomposition reactions • Single replacement reactions • Double replacement reactions • Combustion reactions • You need to be able to identify the type of reaction

5. Types of Reactions • Composition reactions (synthesis) - occurs when two substances (generally elements) combine and form a compound. reactant + reactant  1 product • Basically: A + B  AB • Example: 2H2 + O2  2H2O • Example: C+ O2  CO2

6. 2. Decomposition Reactions • Decomposition reactions - occurs when a compound breaks up into the elements. 1 Reactant  Product + Product In general: AB  A + B • Example: 2 H2O  2H2 + O2 • Example: 2 HgO  2Hg + O2

7. 3. Single Replacement Reactions • Single Replacement Reactions - occurs when one element replaces another in a compound. • A metal can replace a metal (+) OR a nonmetal can replace a nonmetal (-). • element + compound  product + product A + BC  AC + B(if A is a metal)OR A + BC  BA + C (if A is a nonmetal) (remember the cation always goes first!)

8. 4. Double Replacement Reactions • Double Replacement Reactions - occurs when a metal replaces a metal in a compound or a nonmetal replaces a nonmetal in a compound • Compound + compound  product + product • AB + CD  AD + CB (metals are blue, non-metals are red) • Example: • LiCl + Na2O  Li2O + NaCl

9. 5. Combustion Reactions • Combustion reactions occur when a hydrocarbon reacts with oxygen gas. • This is also called burning!!! In order to burn something you need the 3 things in the “fire triangle”:1) A Fuel (hydrocarbon)2) Oxygen to burn it with3) Something to ignite the reaction (spark)

10. Combustion Reactions • In general: CxHy + O2  CO2 + H2O • Products in combustion are ALWAYS carbon dioxide and water. (although incomplete burning does cause some by-products like carbon monoxide) • Combustion is used to heat homes and run automobiles (octane, as in gasoline, is C8H18)

11. H2 + Cl2 HCl

12. KI + Br2 KBr + I2

13. Mg + O2 MgO

14. H2CO3 CO2 + H2O

15. AgNO3 + NaCl  AgCl + NaNO3

16. Li + H2O  LiOH + H2

17. CH4 + O2 CO2 + H2O

18. FeS + HCl  FeCl2 + H2S

19. KClO3 KCl + O2

20. Zn + HCl  ZnCl2 + H2

21. Mg(NO3)2 + KOH  Mg(OH)2 + KNO3

22. C3H8 + O2 CO2 + H2O

23. Identify the Type of Reaction • Na(s) + Cl2(g)  NaCl (s) • K (s) + Cl2(g)  KCl (s) • PbO2(s)  Pb (s) + O2(g) • Fe2O3(s) + Al (s)  Al2O3(s) + Fe (s) • C2H2(g) + O2 (g)  CO2 (g) + H2O (l) • Ba3N + K2S  BaS + K3N

24. Identify the Type of Reaction • Exit Slip- Identify the types of reactions • Ca(s) + Cl2(g)  CaCl2(s) • HCl (aq) + Na (s)  H2(g) + NaCl (aq)

25. Identify the Type of Reaction • HOMEWORK: page 284 #1-2

26. Steps to Writing Reactions • Some steps for writing reactions • Identify the type of reaction • Predict the product(s) using the type of reaction as a model (DON’T FORGET TO CROSS THE CHARGES). • Balance it Don’t forget about the diatomic elements! (BrINClHOF) For example, Oxygen is O2 as anelement.

27. Synthesis Practice • Predict the products. Write and balance the following synthesis reaction equations. • Sodium metal reacts with chlorine gas Na(s) + Cl2(g)  • Solid Magnesium reacts with fluorine gas Mg(s) + F2(g)  • Aluminum metal reacts with fluorine gas Al(s) + F2(g) 

28. Decomposition Exceptions • Carbonates and chlorates are special case decomposition reactions that do not go to the elements. • Carbonates (CO32-) decompose to carbon dioxide and a metal oxide • Example: CaCO3  CO2 + CaO • Chlorates (ClO3-) decompose to oxygen gas and a metal chloride • Example: 2 Al(ClO3)3  2 AlCl3 + 9 O2

29. Decomposition Practice • Predict the products. Then, write and balance the following decomposition reaction equations: • Solid potassium chlorate decomposes KClO3(s)  • Aluminum nitride decomposes AlN(s) 

30. Practice Identify the type of reaction for each of the following synthesis or decomposition reactions, and write the balanced equation: BaCO3(s)  Co(s) (III) + S(s)  NI3(s) 

31. Homework Identify the type of reaction for each of the following and balanced ___ NaBr + ___ H3PO4 ___ Na3PO4 + ___ HBr __ Ca(OH)2 + __ Al2(SO4)3 __ CaSO4 + __ Al(OH)3 ____ Mg + ____ Fe2O3 ____ Fe + ____ MgO ____ C2H4 + ____ O2 ____ CO2 + ____ H2O ___ H2 + ___ O2  ____ H2O ___ Ca + ____ O2  ____ CaO ____ KCl  ____ K + ____ Cl2

32. Homework Identify the reaction type, predict the products and balance. NaClO3 Li + N2  BaO  Fe (III) + Cl 

33. Single Replacement Reactions • Write and balance the following single replacement reaction equation: • Zinc metal reacts with aqueous hydrochloric acid Zn(s) (II)+ HCl(aq) Note: Zinc replaces the hydrogen ion in the reaction

34. Single Replacement Reactions • Sodium chloride solid reacts with fluorine gas NaCl(s) + F2(g)  Note that fluorine replaces chlorine in the compound • Aluminum metal reacts with aqueous copper (II) nitrate Al(s)+ Cu(NO3)2(aq)

35. Double Replacement Reactions • Example: AgNO3(aq) + NaCl(s)  • Another example: K2SO4(aq) + Ba(NO3)2(aq)  2

36. Practice • Predict the products. Balance the equation • HCl(aq) + AgNO3(aq)  • Pb(NO3)2(aq) + BaCl2(aq)  • FeCl3(aq) + Na(s)  • CaCl2(aq) + Na3PO4(aq)  • K(s) + CuSO4(aq) 

37. Combustion • Example • C5H12 + O2 CO2 + H2O • Write the products and balance the following combustion reaction: • C10H22 + O2 

38. Mixed Practice • State the type, predict the products, and balance the following reactions: • BaCl2 + H2SO4 • C6H12 + O2  • Zn + CuSO4  • Cs + Br2  • FeCO3 

39. Exit Slip • Predict products, identify type of reaction, and balance • Mg + HNO3