Unit 4 - Chemical Reactions - Review Sheet

Note: This review is not meant to replace studying your notes, but is a good overview of the various topics covered in this unit.

Part A - Name the conservation laws (if any) that are being broken

  1. Ag2+ + Cl-AgCl
  2. Mg + 2 H+Mg+ + H2
  3. 2 HCl + NaOH 2 NaCl + H2O
  4. 2.1 g of sodium hydroxide pellets react with 1.3 g of sulphuric acid to produce 1.1 g of sodium sulphate and 2.7 g of water.
  5. 1 mol of sodium chloride decomposes into 1 mol of sodium and 1 mol of chlorine.(Hint: write out the chemical equation!)
  6. A person lives on nothing but water for an entire month.
  7. H2O(s) + energy H2O(l)
  8. C5H12 + 8 O25 CO2 + 6 H2O
  9. A closed system contains more heat energy after a reaction compared to before the reaction.
  10. While in Wonderland, Alice eats a piece of a mushroom and suddenly grows to ten times her usual size.

Part B - Balance the reactions

  1. ___H2 + ___Cl2 ___HCl
  2. ___N2 + ___H2 ___NH3
  3. ___Na + ___H2O ___NaOH + ___H2
  4. ___NH3 + ___O2 ___N2 + ___H2O
  5. ___C6H14 + ___O2 ___CO2 + ___H2O
  6. ___KNO3 ___KNO2 + ___O2
  7. ___Be2C + ___H2O ___Be(OH)2 + ___CH4
  8. ___NpF3 + ___O2 + ___HF ___NpF4 + ___H2O
  9. ___NO2 + ___H2O ___HNO3 + ___NO
  10. ___LiAlH4 + ___BF3 ___LiF + ___AlF3 + ___B2H6

Part C - Write the balanced chemical equation, including phases, for each description

  1. Sodium nitrate crystals and solid sodium metal react to form solid sodium oxide and nitrogen gas.
  2. Gaseous boron trichloride reacts with steam to yield solid boron trihydroxide and hydrogen chloride gas.
  3. Gaseous xenon hexafluoride reacts violently with water to form solid xenon trioxide and gaseous hydrogen fluoride.
  4. Aluminum metal dissolves in an aqueous solution of sulfuric acid to form hydrogen gas bubbles and a solution of aluminum sulfate.
  5. When beryllium chloride reacts with silver nitrate (both dissolved in water), aqueous beryllium nitrate and silver chloride powder are made.

Part D - Classify the reaction andpredict the products

  1. C6H4(OH)2 + O2
  2. AlCl3 + Na2CO3
  3. Ba(OH)2 + H2SO4
  4. Cl2 + CaBr2
  5. ZnSO4 + SrCl2
  6. NH3
  7. HI
  8. Mg + HCl
  9. H4P2O7 + KOH
  10. Co(NO3)2 + H2S

Part E - Exothermic or endothermic?

  1. A + 63 kJ → B
  2. Cooking food.
  3. Decomposition.
  4. Heat energy leaves the system.
  5. Synthesis.
  6. The formation of ice.
  7. The products have more energy than the reactants.
  8. The reaction vessel feels warm.
  9. The system becomes warmer.
  10. ΔH is negative.

Answers

Part A: 1. electrical charge, 2. electrical charge, 3. atoms and mass, 4. mass and atoms,

5. atoms and mass, 6. energy, 7. none, 8. none, 9. energy, 10. mass and atoms

Part B: 1.1,1,2, 2. 1,3,2, 3. 2,2,2,1, 4. 4,3,2,6, 5. 2,19,12,14, 6. 2,2,1, 7. 1,4,2,1, 8. 4,1,4,4,2, 9. 3,1,2,1, 10. 3,4,3,3,2

Part C: 1. 2 NaNO3(s) + 10 Na(s) 6 Na2O(s) + N2(g), 2. BCl3(g) + 3 H2O(g) B(OH)3(s) + 3 HCl(g), 3. XeF6(g) + 3 H2O(l) XeO3(s) + 6 HF(g), 4.2 Al(s) + 3 H2SO4(aq) 3 H2(g) + Al2(SO4)3(aq), 5. BeCl2(aq) + 2 AgNO3(aq) Be(NO3)2(aq) + 2 AgCl(s)

Part D: 1. combustion, CO2 + H2O, 2. double replacement, Al2(CO3)3 + NaCl, 3. neutralization, Ba(SO4) + H2O, 4. single replacement, Br2 + CaCl2, 5. double replacement, SrSO4 + ZnCl2, 6. decomposition, N2 + H2, 7. decomposition, H2 + I2, 8. single replacement, H2 + MgCl2, 9. neutralization, K4P2O7 + H2O, 10. double replacement, CoS + HNO3

Part E: 1. endo, 2. endo, 3. endo, 4. exo, 5. exo, 6. exo, 7. endo, 8. exo, 9. endo, 10. exo