1 / 30

Types of Chemical Rxns

Types of Chemical Rxns. Composition (Synthesis) Rxns. Two or more substances react to form a single, more complex substance. Examples:. 2 Hg + O 2. 2HgO. 2Ag + S. Ag 2 S. Movie of Potassium + Bromine. Decomposition Reactions. A Complex Substance is Broken Down

johnavila
Download Presentation

Types of Chemical Rxns

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Types of Chemical Rxns

  2. Composition (Synthesis) Rxns Two or more substances react to form a single, more complex substance. Examples: 2 Hg + O2 2HgO 2Ag + S Ag2S Movie of Potassium + Bromine

  3. Decomposition Reactions A Complex Substance is Broken Down (usually by heating) into 2 or more smaller substances Which Side does energy term go on? ____thermic endo Examples MnO2 KClO3 + heat 2 2 KCl + O2 3 ªH BaCl2 + 2H2O BaCl2 2H2O MnO2 2 + heat H2O (l) + O2(g) H2O2 (aq) 2 Movie of Nitrogen TriIodide

  4. Single Replacement Rxns A single element takes the place of another element in a compound Examples: Zn + HCl H2 + ZnCl2 2 2 Cu + AgNO3 2 Ag + Cu(NO3)2 Movie of Thermite Reaction

  5. Double Replacement RxnSometimes called Exchange or Metathesis Rxns The ions in two aqueous compounds swap partners Examples: AgCl(9) + NaNO3(aq) AgNO3(aq) + NaCl(aq) Calcium chloride + Potassium Nitrate Potassium chloride + Calcium nitrate See formula Movie of sodium iodide + lead(II) nitrate

  6. 2 2 CaCl2(aq) + KNO3(aq) KCl(aq) + Ca(NO3)2(s) Back

  7. Combustion Rxns A hydrocarbon reacts with oxygen to produce water and carbon dioxide Usually used for the large amount of heat given off! ___thermic Balancing Tip: Do carbon 1st, then hydrogen, then oxygen Examples: exo 2 CH4 + O2 2 H2O + CO2 + heat C2H5OH + O2 3 3 H2O + CO2 + heat 2

  8. Combustion Rxns Most reactions that we think of as ‘burning’ a fuel are combustion reactions Hydrocarbon Hydrocarbon Hydrocarbon Hydrocarbon Hydrocarbon • Examples: • Burning a log of Wood to heat your s’mores • Burning Coal to heat water to create electricity at a power plant • Grilling with Propane to heat your hot dog • Burning Gasoline in your car to heat the air and push pistons • Burning Oil in your furnace to heat your house

  9. Combustion Rxns Some downsides to combustion reactions: • Fossil Fuels are non-renewable resources • We are using them much faster than they are being produced • Eventually, we will run out of fossil fuels

  10. Combustion Rxns Some downsides to combustion reactions: CO2 is a greenhouse gas and increasing CO2 levels contributes to global warming – (others are methane, water vapor, ozone, nitrous oxide) Our widespread burning of fossil fuels over the last hundred years has increased the earth’s CO2 levels

  11. Combustion Rxns Some downsides to combustion reactions: • Combustion will be “incomplete” when not enough oxygen is present • Complete Combustion • Hydrocarbon + O2 • Incomplete combustion results in CO, Carbon (soot), and nitrous oxides • Hydrocarbon + O2 C + CO +H2O + CO2 • CO is poisonous • Nitrous oxides are bad for the environment (acid rain, smog) + CO2 H2O

  12. Combustion Rxns What can be done? • Incomplete combustion can be improved by better designed burners / engines • Catalytic converters in vehicle reduce CO • “Scrubbers” placed in industrial exhaust systems can reduce nitrous oxides and CO None of these “fixes” cuts down or removes CO2 emissions Balancing Combustion

  13. Identify each reaction type (sr, dr, comp , decomp, combust) A) + + + B) C O2 H O2 C H O + C) + D) + + + E)

  14. A Closer Look: Composition Rxns • Aluminum + oxygen • Calcium oxide + water • Sulfur + oxygen

  15. More Composition Rxns • Sn + O2 -----> • Sodium + chlorine----> • SO3 + H2O --------> • Lithium oxide + water--> • Silicon + oxygen

  16. More Composition RxnsAnswers • Sn + O2 ----->SnO2 • 2Na + Cl2 ---> 2NaCl • SO3 + H2O --------> H2SO4 • Li2O + H2O ------> 2LiOH • Si + O2 -----> SiO2

  17. Decomposition Rxns • CuSO4 5H2O • NaHCO3 • HNO3

  18. More Decomposition Rxns • Na2CO3 ----> • MgO -----> • MgSO4 7H2O ----> • Sr(NO3)2 ----> • H2CO3 ---->

  19. More Decomposition Rxns (Answers) • Na2CO3 ----> Na2O + CO2 • 2MgO -----> 2Mg + O2 • MgSO4*7H2O ----> MgSO4 + 7H2O • Sr(NO3)2 ----> Sr(NO2)2 + O2 • H2CO3 ----> H2O + CO2

  20. Warm-Up: Complete and Balance C2H6 + O2 CO2 + H2O 2 3 7 oxygens Can I get 7 Oxygens here?

  21. Balancing Combustion Rxns 5 PBJ Sandwiches = ____ slices of bread 10

  22. Balancing Combustion Rxns 5 half PBJ Sandwiches = ____ slices of bread 5 5 pairs x ½ = 5 singles

  23. Balancing Combustion Rxns 5 half O2 molecules = ____ atoms of O 5 5 pairs x ½ = 5 singles

  24. Balancing Combustion Rxns 7/2 O2 molecules = ____ atoms of O 7 7 pairs x ½ = 7 singles

  25. 7 2 Warm-Up: Complete and Balance C2H6 + O2 CO2 + H2O 2 3 7 oxygens Total of 7 O’s

  26. Your Turn: • Complete # 10-12 on Page 14 in your packet

More Related