chem lesson 8

• Reaction of Magnesium with Oxygen

  1. Polish magnesium ribbon with steel wool

  2. Light BBQ lighter

  3. Hold magnesium ribbon in flame for 20-30s

  4. Remove wire from flame and allow to cool
• The formula for magnesium oxide is MgO because magnesium has a charge of 2+ and oxygen has a charge of 2-. These two ions want to make a neutral charge.
• Word Equation


  Magnesium + Oxygen → Magnesium Oxide
• Chemical Equation


  2Mg + O2 → 2MgO
• Decomposition of Hydrogen Peroxide

  1. Place test tube in rack

  2. Add hydrogen peroxide to 1/3 full

  3. Add manganese dioxide

  4. Test gas produced by holding glowing splint
• Evidence that hydrogen peroxide decomposed into simpler substances
• Word Equation


  Hydrogen Peroxide → Liquid Water + Oxygen
• Chemical Equation


  2H2O2 → 2H2O + O2
• Single Displacement Reactions


  1. Half-fill 3 wells with copper(II) chloride, add copper/zinc/magnesium

  2. Half-fill 3 wells with zinc chloride, add copper/zinc/magnesium

  3. Half-fill 3 wells with magnesium nitrate, add copper/zinc/magnesium

  4. Observe wells for several minutes
• Chemical Equation 1


  Cu + 2AgNO3 → Cu(NO3)2 + 2Ag

  
• Chemical Equation 2


  Zn + 2HCl → ZnCl2 + H2
• Chemical Equation 3


  2Na + 2HCl → 2NaCl + H2
• Activity series for halogens: F > Cl > Br > I
• Word Equation


  Chlorine + Sodium Bromide → Sodium Chloride + Bromine
• Chemical Equation


  Cl2 + 2NaBr → 2NaCl + Br2
• Double Displacement Reactions


  1. Place copper(II) sulfate and sodium hydroxide in wells

  2. Place silver nitrate and sodium chloride in wells

  3. Wait and record observations
• Chemical Equation 1


  CuSO4 + 2NaOH → Cu(OH)2 + Na2SO4
• Chemical Equation 2


  AgNO3 + NaCl → AgCl + NaNO3

  
• Synthesis: Aluminum + Oxygen → Aluminum Oxide


  2Al + 3/2 O2 → Al2O3
• Synthesis: Sodium + Fluorine → Sodium Fluoride

  2Na + F2 → 2NaF
• Decomposition: Magnesium Oxide → Magnesium + Oxygen


  2MgO → 2Mg + O2
• Decomposition: Iron(III) Oxide → Iron + Oxygen


  2Fe2O3 → 4Fe + 3O2
• Single Displacement: Lithium + Aluminum Chloride → Lithium Chloride + Aluminum


  2Li + 2AlCl3 → 2LiCl + 2Al
• Single Displacement: Calcium + Lead(II) Nitrate → Calcium Nitrate + Lead


  Ca + Pb(NO3)2 → Ca(NO3)2 + Pb
• Synthesis: Potassium + Bromine → Potassium Bromide


  2K + Br2 → 2KBr
• Decomposition: Manganese(IV) Nitride → Manganese + Nitrogen


  Mn3N2 → 3Mn + N2
• Single Displacement: Sodium + Lead(IV) Chloride → Sodium Chloride + Lead

  2Na + PbCl4 → 2NaCl + Pb
• Double Displacement: Nickel(II) Sulfide + Lithium Fluoride → Nickel(II) Fluoride + Lithium Sulfide

  NiS + 2LiF → NiF2 + Li2S