Download 5 • Chemical Reactions

South Pasadena • Honors Chemistry
Name
5 • Chemical Reactions
Period
5.1
PROBLEMS
–
TYPES OF
Date
REACTIONS
1. Classify each reaction as Combustion (C), Decomposition (D), Double Replacement (DR), Single
Replacement (SR), or Synthesis (S). Then balance each equation.
(a) …Al (s) + … Br2 (ℓ)  … AlBr3 (s)
Synthesis
2 Al (s) + 3 Br2 (ℓ)  2 AlBr3 (s)
(b) …C3H7OH (ℓ) + …O2 (g)  …CO2 (g) + … H2O (ℓ)
Combustion
2 C3H7OH (ℓ) + 9 O2 (g)  6 CO2 (g) + 8 H2O (ℓ)
(c) …Ca (s) + …HCl (aq)  …CaCl2 (aq) + …H2 (g)
Single Replacement
Ca (s) + 2 HCl (aq)  CaCl2 (aq) + H2 (g)
(d) …CaBr2 (aq) + …Na2CO3 (s)  …CaCO3 (s) + …NaBr (aq)
Double Replacement CaBr2 (aq) + Na2CO3 (s)  CaCO3 (s) + 2 NaBr (aq)
(e) …(NH4)2CO3 (s)  …NH3 (g) + …CO2 (g) + …H2O (ℓ)
Decomposition
(NH4)2CO3 (s)  2 NH3 (g) + CO2 (g) + H2O (ℓ)
(f) …C3H6O (g) + …O2 (g)  …CO2 (g) + … H2O (ℓ)
Combustion
C3H6O (g) + 4 O2 (g)  3 CO2 (g) + 3 H2O (ℓ)
(g) …Cu2O (s)  …Cu (s) + …O2 (g)
Decomposition
2 Cu2O (s)  4 Cu (s) + O2 (g)
(h) …Fe (s) + … O2 (g)  … Fe2O3 (s)
Synthesis
4 Fe (s) + 3 O2 (g)  2 Fe2O3 (s)
(i) …K2CO3 (s) + …Ca(NO3)2 (aq)  …KNO3 (aq) + …CaCO3 (s)
Double Replacement K2CO3 (s) + Ca(NO3)2 (aq)  2 KNO3 (aq) + CaCO3 (s)
(j) …Al (s) + …Ag2SO4 (aq)  …Al2(SO4)3 (aq) + …Ag (s)
Single Replacement
2 Al (s) + 3 Ag2SO4 (aq)  Al2(SO4)3 (aq) + 6 Ag (s)
2. Write the skeleton equation for each reaction below. Classify each reaction as Combustion (C),
Decomposition (D), Double Replacement (DR), Single Replacement (SR), or Synthesis (S). Then balance the
equation.
(a) Hydrogen gas is combined with oxygen gas.
Synthesis
2 H2 (g) + O2 (g)  2 H2O (ℓ)
(b) Gaseous hydrogen iodide is heated strongly.
Decomposition
2 HI (g)  H2 (g) + I2 (s)
(c) Solutions of sodium phosphate and strontium chlorate are mixed to form a solution of sodium chlorate
and a strontium phosphate precipitate.
Double Replacement 2 Na3PO4 (aq) + 3 Sr(ClO3)2 (aq)  6 NaClO3 (aq) + Sr3(PO4)2 (s)
(d) Strontium metal is placed in an aqueous solution of cuprous bromide to form copper metal and aqueous
strontium bromide.
Single Replacement
Sr (s) + 2 CuBr (aq)  2 Cu (s) + SrBr2 (aq)
(e) Liquid benzene (C6H6) is burned in air.
Combustion
2 C6H6 (ℓ) + 15 O2 (g)  12 CO2 (g) + 6 H2O (ℓ)
(f) Solid potassium chlorate was strongly heated to form solid potassium chloride and oxygen gas.
Decomposition
2 KClO3 (s)  2 KCl (s) + 3 O2 (g)
(g) Solutions of sodium bromide and lead(II) acetate were combined, forming aqueous sodium acetate and
solid lead(II) bromide.
Double Replacement 2 NaBr (aq) + Pb(C2H3O2)2 (aq)  2 NaC2H3O2 (aq) + PbBr2 (s)
(h) Solid sulfur (S8) reacts in oxygen gas to form gaseous sulfur dioxide.
Synthesis
S8 (s) + 8 O2 (g)  8 SO2 (g)
(i) Solid sodium metal is placed in water to form hydrogen gas and a solution of sodium hydroxide.
Single Replacement
2 Na (s) + 2 H2O (ℓ)  H2 (g) + 2 NaOH (aq)
(j) Solid glucose, C6H12O6, reacts with oxygen.
Combustion
C6H12O6 (s) + 6 O2 (g)  6 CO2 (g) + 6 H2O (ℓ)
3. Write the balanced equations for the following synthesis or decomposition reactions.
(a) Synthesis of gaseous nitrogen dioxide.
N2 (g) + 2 O2 (g)  2 NO2 (g)
(b) Solid aluminum oxide is strongly heated.
2 Al2O3 (s)  4 Al (s) + 3 O2 (g)
(c) Liquid phosphorous trichloride is decomposed.
2 PCl3 (ℓ)  2 P (s) + 3 Cl2 (g)
or
4 PCl3 (ℓ)  P4 (s) + 6 Cl2 (g)
(d) Formation of gaseous ammonia (NH3).
N2 (g) + 3 H2 (g)  2 NH3 (g)
(e) Solid copper(I) oxide is strongly heated.
2 Cu2O (s)  4 Cu (s) + O2 (g)
(f) Zinc metal reacts with chlorine gas.
Zn (s) + Cl2 (g)  ZnCl2 (s)
(g) Decomposition of gaseous sulfur trioxide.
2 SO3 (g)  2 S (s) + 3 O2 (g)
or
8 SO3 (g)  S8 (s) + 12 O2 (g)
(h) Formation of sodium oxide.
4 Na (s) + O2 (g)  2 Na2O