Name: MANTARA, MOH.FAHRKY A.
Section: BS CRIM 3-CHARLIE
Work/Practice Exercise:
In substitution to the activity given in a manual, do the following activities:
A. Convert the following worded equations into a chemical equation and balance. Write the
reactants on the left side of the equation and the products on the right side of the equation and
indicate the physical state of each substance involved.
1. Solid ammonium carbonate is heated. It decomposes into ammonia gas, carbon dioxide gas and
water vapor.
(NH4)2 CO3 (s) + HEAT Δ 2NH3(g) + CO2 (g) + H2O(g)
N=2 N = 1x2=2
H = 4x2=8 H = 3x2=6+2=8
C=1 C =1
O= 3 O=2+1=3
2. Ethyl alcohol (CH3CH2OH) and carbon dioxide gas can be produced by the fermentation of
glucose (C6H12O6) with the presence of yeast.
C6H12O6 (aq) 2C2H5OH2 (aq) + 2CO2(g)
C=6 C = 2x2=4+2=6
H = 12 H = 2x5=10+2=12
O=6 O = 2x2= 4+2=6
3. Liquefied propane gas is often used for cooking in suburban areas away from natural gas lines.
Propane (C3H8) burns in oxygen gas, producing carbon dioxide gas, water vapor and heat.
C3H8(g) + 5O2(g) Δ 3CO2(g) + 4H2O(g)
C=3 C=3
H=8 H = 4x2=8
O=10 O = 3x2=6+4=10
4. Iron metal reacts with oxygen gas in air to form iron (III) oxide.
2FE2O3(s) 4FE(s) + 3O2(g)
Fe = 2x2 = 4 Fe = 4
O = 2x3 = 6 O = 3x2 = 6
5. Silver nitrate is used in “styptic pencils” which help to cauterize small nicks and cuts occurring
during shaving. Silver nitrate can be prepared by dissolving metallic silver in concentrated nitric
acid with hydrogen gas being an additional product of the reaction.
2Ag(s) + 2HNO3(aq) 2AgNO3(aq) + H2(g)
Ag = 2 Ag = 2
H=2 H=2
N =2 N= 2
O = 2x3=6 O= 2x3=6
B. Balance the equation and classify the following as combination/synthesis or decomposition or
single displacement/substitution or double displacement reaction:
Chemical Equations Balance the reaction Classification
CuSO4(aq) + Zn(s) → ZnSO4(aq) + Cu(s) single
Cu = 1 Cu=1 displacement
1. CuSO4(aq) + Zn(s) → ZnSO4(aq) +
S =1 S=1
Cu (s) /substitution
O=4 O=4
Zn= 1 Zn=1 reaction
MgO(s) + H2O(l) → Mg (OH)2(aq) Direct
M=1 M=1 combination/
2. MgO(s) + H2O(l) → Mg (OH)2(aq)
O=2 O=2
Synthesis reaction
H =2 H=2
KCl(aq) + AgNO3(aq) KNO3(aq) + AgCl(↓) double
K = 1 K= 1 displacement
3. KCl(aq) + AgNO3(aq) → KNO3(aq)
Cl = 1 Cl = 1
+ AgCl (↓) reaction
Ag = 1 Ag = 1
N=1 N=1
O=3 O =3
CuSO4•H2O(s)+heat →CuSO4+ H2O(g) Decomposition
Cu = 1 Cu= 1 reaction
4. CuSO4•H2O(s) + heat → CuSO4 +
S =1 S= 1
H 2O(g) O= 4 O=4
H=2 H= 2
6HCl(aq) + 2Al(s) → 2AlCl3 + H2(g) single
Al = 1x2=2 Al = 1x2=2 displacement
5. HCl(aq) + Al(s) → AlCl3 + H2(g)
H= 1x6=6 H= 2x3=6
/substitution
Cl = 1x6=6 Cl= 3x2=6
reaction
CuSO4(aq)+Fe(s) → FeSO4(aq) +Cu(s) single
Cu = 1 Cu= 1 displacement
6. CuSO4(aq) + Fe(s) → FeSO4(aq) +
S=1 S=1
Cu (s) /substitution
O=4 O=4
Fe = 1 Fe = 1 reaction
(CH3COO)2Pb(aq)+K2CrO4(aq)→2CH3COOK(aq) double
+PbCrO4(↓)
7. (CH3COO)2Pb(aq) + K2CrO4(aq) → displacement
C = 2+2=4+1=5 C = 2+2=4+1=5
CH3COOK(aq) + PbCrO4(↓) H = 3x2=6 H= 2x3= 6
reaction
O = 4+4=8 O = 4+4 = 8
K=2 K=2
Pb = 1 Pb = 1
Cr = 1 Cr = 1
Li2SO4(aq) + BaCl2(aq) → BaSO4(↓)+2LiCl double
Li = 2 Li= 1x2 displacement
8. Li2SO4(aq) + BaCl2(aq) → BaSO4(↓)
S=1 S= 1
+ LiCl reaction
O=4 O=4
Ba = 1 Ba= 1
Cl = 2 Cl= 1x2=2
Cu(s) + O2(g) → Cu2O(s) Decomposition
9. Cu(s) + Heat → CuO(s) Cu = 1 Cu = 1 reaction
O =2 O = 1x2=2
CH3CH2OH(l) + 3O2 → 2CO2(g) + 3H2O(g) Decomposition
C=2 C = 1x2=2 reaction
10. CH3CH2OH(l) + heat → CO2(g) +
H=6 H = 2x3=6
H 2O(g) O = 3x2=6+1=7 O= 4+3= 7
