Problem Set 4.1:       Balancing Equations

Complete each equation by writing each balancing coefficient. Each blank should have a whole number!

 

1.       __2_ Sb              +        __5_ Cl2             à       __2_ SbCl5

2.       __2_ FeCl2              +        __1_ Cl2             à       __2_ FeCl3

3.       __1_ P4              +        __6_ I2               à       __4_ PI3

4.       __1_ Na2S          +        __2_ HCl           à       __2_ NaCl          +       __1_ H2S

5.       __3_ NaOH       +        __1_ FeCl3         à       __3_ NaCl          +       __1_ Fe(OH)3

6.       __3_ KOH         +        __1_ H3PO4       à       __1_ K3PO4       +       __3_ H2O

7.       __2_ NaOH       +        __1_ CuSO4       à       __1_ Na2SO4         +       __1_ Cu(OH)2

8.       __2_ HNO3        +        __1_ Ca(OH)2    à       __2_ H2O           +       __1_ Ca(NO3)2

9.       __2_ NH3           +        __3_ CuO          à       __3_ H2O           +       __3_ Cu +                         __1_ N2

10.    __4_ NH3           +        __5_ O2              à       __4_ NO            +       __6_ H2O

11.    __4_ NH3           +        __7_ O2              à       __4_ NO2           +       __6_ H2O

12.    __2_ NH3           +        __4_ O2              à       __1_ N2O5         +       __3_ H2O

13.    __1_ P4              +        __10_ N2O         à       __2_ P2O5          +       __10_ N2

14.    __2_ Al              +        __6_ HCl           à       __2_ AlCl3         +       __3_ H2

15.    __1_ Zn             +        __2_ KOH         à       __1_ K2ZnO2     +       __1_ H2

16.    __1_ B2O3          +        __3_ Mg            à       __3_ MgO         +       __2_ B

17.    __2_ CH3OH     +        __3_ O2              à       __4_ H2O           +       __2_ CO2

18.    __1_ C6H12O6                                         à       __2_ C2H5OH    +       __2_ CO2

19.    __2_ Na             +        __2_ H2O           à       __2_ NaOH       +       __1_ H2

20.    __2_ PbS            +        __3_ O2                     à       __2_ PbO           +       __2_ SO2

21.    __1_ SiCl4          +        __4_ Na             à       __1_ Si               +       __4_ NaCl

22.    __2_ Mg            +        __1_ CO2           à       __2_ MgO         +       __1_ C

23.    __2_ Al              +        __3_ H2SO4       à       __1_ Al2(SO4)3  +       __3_ H2

24.    __1_ N2              +        __4_C        + __1_Na2CO3                      à      __2_ NaCN +                         __3_ CO

 

 

Write balanced chemical equations for each word equation. Include phase symbols for all formulas.

 

25.           Solid sodium oxide plus water yields sodium hydroxide solution.

 

Na2O (s)  +    H2O (l)        à        2 NaOH (aq)

 

 

26.           Barium phosphate plus sodium sulphate (both dissolved in water) yields solid barium sulphate and aqueous sodium phosphate.

 

Ba3(PO4)2 (aq)  +    3 Na2SO4 (aq)             à        3 BaSO4 (s)   +   2 Na3PO4 (aq)

 

 

27.           Lead metal added to sulphuric acid solution produces lead (IV) sulphate precipitate and diatomic hydrogen gas.

 

Pb (s)  +    2 H2SO4 (aq)     à        Pb(SO4)2 (s)  +   2 H2 (g)

 

 

28.           Potassium iodide (aq) plus lead (II) nitrate yields potassium nitrate (aq) plus lead (II) iodide (s).

 

2 KI (aq)  +    Pb(NO3)2 (aq)           à        2 KNO3 (aq)  +  PbI2 (s)

 

 

29.           Solid calcium carbonate plus aqueous hydrochloric acid yields aqueous calcium chloride, carbon dioxide gas and water.

 

CaCO3 (s)   +    2 HCl (aq)            à        CaCl2 (aq) +  CO2 (g)   +   H2O (l)

 

 

30.           Potassium nitrate (aq) plus iron (III) hydroxide (aq) yields iron (III) nitrate (aq) plus potassium hydroxide (aq).

 

3 KNO3 (aq)  +     Fe(OH)3 (aq)     à        Fe(NO3)3 (aq)  +   3 KOH (aq)

 

 

Bonus. Balance these!

 

1. __16_ HCl + __2_ K2CrO4                        à         __4_ KCl  + __2_ CrCl3 +__8_ H2O + __3_ Cl2

 

2. __1_ K2Cr2O7 + __6_ KI +__7_ H2SO4   à          __4_ K2SO4 + __1_ Cr2(SO4)3 + __3_ I2 + __7_ H2O