4.1 – Writing and Balancing Chemical Equations — The Magic of Chemistry
Balancing Chemical Equations, p. 164 Chemical equations need to be balanced in order to maintain the conservation laws
Balancing Chemical Equations, p. 164 Law of conservation of mass In a closed system, the total mass does not change The mass of the products equals the mass of the reactants
Balancing Chemical Equations, p. 164 A balanced chemical equation must ensure the conservation of mass, atoms and electrical charges
Balancing Chemical Equations, p. 164 Coefficients Numbers written before the formula of each reactant and product representing how many particles of each are present Apply to or multiple every element and atom in the particle, not just the first
H2S + PbCl2 PbS + HCl H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl 2 H = 2 H = 1 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl 2 H = 2 H = 2 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 1
H2S + PbCl2 PbS + HCl 2 H = 2 H = 2 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 2
H2S + PbCl2 PbS + HCl 2 H = 2 H = 2 S = 1 S = 1 Pb = 1 Pb = 1 Cl = 2 Cl = 2
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 1 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 5 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 13 H = 5 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 15 H = 5 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 15 H = 5 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 1 H = 15 H = 5 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 5 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 11 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 11 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 11 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 11 P = 1 P = 1 O = 7 O = 5 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 15 P = 1 P = 1 O = 7 O = 7 Na = 3 Na = 3
(NH4)3PO4 + NaOH Na3PO4 + NH3 + H2O 15 H = 15 P = 1 P = 1 O = 7 O = 7 Na = 3 Na = 3
C19H17NO3 + O2 CO2 + H2O + N2 C = 19 C = 1 H = 17 H = 2 N = 1 N = 2 O = 5 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 C = 19 C = 1 H = 17 H = 2 N = 1 N = 2 O = 5 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 C = 19 C = 1 H = 17 H = 2 N = 1 N = 2 O = 5 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 C = 19 C = 1 H = 17 H = 2 N = 2 N = 2 O = 5 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 C = 38 C = 1 H = 34 H = 2 N = 2 N = 2 O = 8 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 C = 38 C = 1 H = 34 H = 2 N = 2 N = 2 O = 8 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 1 H = 34 H = 2 N = 2 N = 2 O = 8 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 3
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 C = 38 C = 38 H = 34 H = 2 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 77
C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 93
C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 93
can only add an even amount C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 can only add an even amount C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 93 need an odd number
Balancing Chemical Equations, p. 164 If you need an odd amount of a diatomic element, doubling everything else will produce a need for an even amount
C19H17NO3 + O2 CO2 + H2O + N2 2 38 17 C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 93
C19H17NO3 + O2 CO2 + H2O + N2 4 76 34 2 C = 38 C = 38 H = 34 H = 34 N = 2 N = 2 O = 8 O = 93
C19H17NO3 + O2 CO2 + H2O + N2 4 87 76 34 2 C = 76 C = 76 H = 68 H = 68 N = 4 N = 4 O = 14 O = 186
C19H17NO3 + O2 CO2 + H2O + N2 4 87 76 34 2 C = 76 C = 76 H = 68 H = 68 N = 4 N = 4 O = 186 O = 186
C19H17NO3 + O2 CO2 + H2O + N2 4 87 76 34 2 C = 76 C = 76 H = 68 H = 68 N = 4 N = 4 O = 186 O = 186
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 S = 3 S = 1 O = 16 O = 7 K = 2 K = 2 I = 2 I = 2 H = 2 H = 3
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 S = 3 S = 1 O = 16 O = 7 K = 2 K = 2 I = 2 I = 2 H = 2 H = 3
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 S = 3 S = 1 O = 16 O = 7 K = 2 K = 2 I = 2 I = 2 H = 2 H = 3
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 O = 16 O = 10 K = 2 K = 2 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 O = 16 O = 10 K = 2 K = 2 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 1 O = 16 O = 10 K = 2 K = 2 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 16 O = 18 K = 2 K = 6 I = 2 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 16 O = 18 K = 6 K = 6 I = 6 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 16 O = 18 K = 6 K = 6 I = 6 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 16 O = 18 K = 6 K = 6 I = 6 I = 2 H = 2 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 18 O = 18 K = 6 K = 6 I = 6 I = 2 H = 6 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 18 O = 18 K = 6 K = 6 I = 6 I = 2 H = 6 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 18 O = 18 K = 6 K = 6 I = 6 I = 2 H = 6 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 18 O = 18 K = 6 K = 6 I = 6 I = 6 H = 6 H = 6
Cr2(SO4)3 + KI + KIO3 + H2O Cr(OH)3 + K2SO4 + I2 5 3 2 3 3 Cr = 2 Cr = 2 S = 3 S = 3 O = 18 O = 18 K = 6 K = 6 I = 6 I = 6 H = 6 H = 6
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 4 Cl = 4 O = 2 O = 1 Ag = 1 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 4 Cl = 4 O = 2 O = 1 Ag = 1 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 4 Cl = 4 O = 2 O = 1 Ag = 1 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 5 Cl = 4 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 5 Cl = 4 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 1 Cl = 5 Cl = 4 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 2 Cl = 5 Cl = 8 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 2 Cl = 5 Cl = 8 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 1 Mo = 2 Cl = 5 Cl = 8 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 8 Cl = 8 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 8 Cl = 8 O = 2 O = 1 Ag = 2 Ag = 2
MoCl3 + O2 + AgCl MoCl4 + Ag2O 16 Cl = 16 O = 2 O = 2 Ag = 4 Ag = 4
MoCl3 + O2 + AgCl MoCl4 + Ag2O 16 Cl = 16 O = 2 O = 2 Ag = 4 Ag = 4
Keeping Your Balance — Helpful Hints, p. 165 Write a properly balanced equation for the following chemical reaction: Copper(I) oxide and carbon react to form copper and carbon dioxide 2Cu2O + C 4Cu + CO2