Assignment 6 - Answer Key

1. List four signs that a chemical reaction has occurred: a) gas produced b) insoluble solid produced c) permanent color change d) energy change

2. Write chemical equations for the following: a) magnesium metal combining with bromine to give solid magnesium bromide Mg(s) + Br2(l)  MgBr2(s)

b) zinc hydrogen carbonate decomposes to give solid zinc carbonate, water, and carbon dioxide gas Zn(HCO3)2(s)  ZnCO3(s) + H2O(l) + CO2(g)

c) aqueous lithium iodide and aqueous silver nitrate combine to give silver iodide precipitate and aqueous lithium nitrate LiI(aq) + AgNO3(aq)  AgI(s) + LiNO3(aq)

d) nitric acid reacts with aqueous ammonium hydroxide to give aqueous ammonium nitrate plus water HNO3(aq) + NH4OH(aq)  NH4NO3(aq) + H2O(l)

3. Balance each of the following chemical equations: a) __ Al2(CO3)3(s)  __ Al2O3(s) + _3_ CO2(g) b) __ K2SO4(aq) + __ Ba(OH)2(aq)  __ BaSO4(s) + _2_ KOH(aq) c) __ Hg2(NO3)2(aq) + _2_ NaBr(aq)  __ Hg2Br2(s) + _2_ NaNO3(aq) d) __ H2CO3(aq) + _2_ NH4OH(aq)  __ (NH4)2CO3(aq) + _2_ H2O(l)

4. Classify each reaction as one of the following: combination, decomposition, single replacement, double replacement, or neutralization a) 3 Sn(s) + 2 P(s)  Sn3P2(s) __combination______b) 2 HClO4(aq) + Ba(OH)2(s)  Ba(ClO4)2(s) + 2 H2O(l) __neutralization_____ c) Cu(s) + 2 AgC2H3O2(aq)  Cu(C2H3O2)2(aq) + 2 Ag(s) __single replacement__ d) 2 LiClO3(s)  2 LiCl(s) + 3 O2(g) __decomposition______e) Pb(NO3)2(aq) + 2 LiCl(aq)  PbCl2(s) + 2 LiNO3(aq) _double replacement__

5. Based on the activity series (see Chapter 7 lecture slides), predict which of the following reactions does not occur (NR, for no reaction): a) aqueous copper(II) nitrate with nickel b) sulfuric acid with gold NR c) aqueous iron(II) sulfate with silver NR d) hydrochloric acid with zinc

6. Predict the products for each of the following single replacement reactions, and next balance the chemical equations: a) __ Zn(s) + __ Pb(NO3)2(aq)  __Zn(NO3)2(aq) + Pb(s)______b) __ Cd(s) + _2_ HNO3(aq)  __Cd(NO3)2(aq) + H2(g)______

7. Based on the solubility rules (see Chapter 7 lecture slides), predict which of the following compounds are NOT soluble in water: a) aluminum nitrate, Al(NO3)3 b) cobalt(II) hydroxide, Co(OH)2 NOT soluble c) copper(II) sulfate, CuSO4 d) silver bromide, AgBr NOT soluble

8. Predict the products for each of the following double replacement reactions, and next balance the chemical equations: a) _2_ AgC2H3O2(aq) + __ SrI2(aq)  _2 AgI(s) + Sr(C2H3O2)2(aq)______b) __ FeSO4(aq) + __ Ca(OH)2(aq)  __Fe(OH)2(s) + CaSO4(aq)______