Homework, Chapter 8: 3, 9, 13, 21
3. Balance each of the following equations and classify it:
a) 2 H2 + O2  2 H2O
combination;
b) 3 C + Fe2O3  2 Fe + 3 CO
decomposition;
c) H2SO4 + 2 NaOH  2 H2O + Na2SO4
double displacement;
d) Al2(CO3)3  Al2O3 + 3 CO2
decomposition;
e) 2 NH4I + Cl2  2 NH4Cl + I2
single displacement.
9. Change these word equations into formula equations and balance them:
a) water  hydrogen + oxygen
2 H2O  2 H2 + O2
b) acetic acid + potassium hydroxide  potassium acetate + water.
CH3COOH + KOH  CH3COOK + H2O
c) phosphorus + iodine  phosphorus triiodide
2 P + 3 I2  2 PI3
d) aluminum + copper(II) sulfate  copper + aluminum sulfate
2 Al + 3 CuSO4  3 Cu + Al2(SO4)3.
e) ammonium sulfate + barium chloride  ammonium chloride + barium sulfate
(NH4)2SO4 + BaCl2  2 NH4Cl + BaSO4.
f) sulfur tetrafluoride + water  sulfur dioxide + hydrogen fluoride
SF4 + 2 H2O  SO2 + 4 HF
g) chromium(III) carbonate  chromium(III) oxide + carbon dioxide.
Cr2(CO3)3  Cr2O3 + 3 CO2
13. Use the activity series to predict which of the following reactions will occur.
Complete and balance the equations. When no reaction will occur, write “no reaction” as
the product.
Ag(s) + H2SO4(aq)  no reaction
Cl2(g) + 2 NaBr(aq)  2 NaCl(aq) + Br2(l)
Mg(s) + ZnCl2(aq)  MgCl2(aq)+ Zn(s)
Pb(s) + AgNO3(aq)  PbNO3(aq) + Ag(s)
21. Write balanced equations for each of these reactions including the heat term:
a) Lime, CaO, is converted to slaked lime, Ca(OH)2 by reaction with water. The
reaction liberate 65.3 kJ of heat for each mole of lime reacted.
CaO + H2O  Ca(OH)2 + 65.3 kJ
b) The industrial production of aluminum metal from aluminum oxide is an
endothermic electrolytic process requiring 1630 kJ per mole of Al2O3. Oxygen is
also a product.
2 Al2O3 + 1630 kJ  4 Al + 3 O2
Chpt. 6 (p.122): 3, 6, 8, 15, 17, 25, 29
3.
Write formulas for the following cations (don’t forget to indicate charges):
sodium: Na+; magnesium” Mg2+; aluminum Al3+; copper(II): Cu2+; iron(II): Fe2+;
iron(III): Fe3+; lead(II): Pb2+; silver: Ag+; cobalt(II): Co2+; barium: Ba2+;
hydrogen: H+; mercury(II): Hg2+; tin(II): Sn2+; chromium(III): Cr3+; tin(IV):
Sn4+; manganese(II): Mn2+; bismuth(III): Bi3+.
6.
Write the systematic names for the following:
a) slaked lime (Ca(OH)2): calcium(II) hydroxide; b) saltpeter (NaNO3): sodium
nitrate; c) brimstone (S): sulfur; d) baking soda (NaHCO3): sodium hydrogen
carbonate; e) pyrite (FeS2): iron(IV) sulfide; f) potash (K2CO3): potassium
carbonate.
8.
Complete the table, filling each box with the proper formula.
NH4+
Ca2+
Fe3+
Ag+
Cu2+
SO42(NH4)2SO4
CaSO4
Fe2(SO4)3
Ag2SO4
CuSO4
15.
Name these compounds by the Stock (IUPAC) System:
17.
OHNH4OH
Ca(OH)2
Fe(OH)3
AgOH
Cu(OH)2
AsO43(NH4)3AsO4
Ca3(AsO4)2
FeAsO4
Ag3AsO4
Cu3(AsO4)2
C2H3O2NH4C2H3O2
Ca(C2H3O2)2
Fe(C2H3O2)3
AgC2H3O2
Cu(C2H3O2)2
CrO42(NH4)2CrO4
CaCrO4
Fe2(CrO4)3
Ag2CrO4
CuCrO4
a) CuCl2: copper(II) chloride;
b) CuBr: copper(I) bromide;
c) Fe(NO3)2: iron(II) nitrate;
d) FeCl3: iron(III) chloride;
e) SnF2: tin(II) fluoride;
f) HgCO3: mercury(II) carbonate.
Write formulas for these acids:
a) hydrochloric acid: HCl;
b) chloric acid: HClO3;
c) nitric acid: HNO3;
d) carbonic acid: H2CO3;
e) sulfurous acid: H2SO3;
f) phosphoric acid: H3PO4.
25.
Write the chemical formula for these substances:
a) baking soda: NaHCO3;
b) lime: Ca(OH)2;
c) Epsom salts: MgSO4;
d) muriatic acid: HCl;
e) vinegar: HC2H3O2;
f) potash: K2CO3;
g) lye: NaOH.
29.
Write formulas for all possible compounds formed between the calcium ion and
the anions shown in Question 28:
a) CaSO4;
b) Ca3(PO4)2; c) Ca(NO3)2; d) Ca(ClO3)2;
e) Ca(OH)2
f) CaCO3.