REACTION PREDICTION Pre-AP CHEMISTRY

Reactants  Products The arrow means “yields” or “produces”

(s) = solid (g)= gas (l)= liquid (aq)= aqueous (dissolved in water)  = reversible reaction = catalyst (in this case, Pt is the catalyst) = heat is added = heat is added

Practice “translating” a word equation: Solid zinc metal reacts with aqueous copper(II) sulfate to produce solid copper metal and aqueous zinc sulfate. Zn(s) + CuSO4(aq)  Cu(s) + ZnSO4(aq)

Balancing Equations *Balancing is a trial and error process and is best done in pencil!! *We balance an equation so that the reactants and products each have the same number of atoms of each element (conservation of mass). *We must correctly write the formulas for all reactants and products before we balance.

Coefficients = Numbers placed in front of reactants and products 2H2 + O2  2H2O This means that 2 moles or molecules of hydrogen gas react with 1 mole or molecule of oxygen gas to produce 2 moles or molecules of water. The coefficients must be in the lowest ratio.

Hints:. Balance elements one at a time Hints: *Balance elements one at a time. *Balance polyatomic ions that appear on both sides of the equation as single units. (Ex. Count sulfate ions, not sulfur and oxygen separately) *Balance H and O last.

Zn + HCl  ZnCl2 + H2 Zn + 2HCl  ZnCl2 + H2

Al2(SO4)3 + Ca(OH)2  Al(OH)3 + CaSO4

K + H2O  KOH + H2 2K + 2H2O  2KOH + H2

CH4 + O2  CO2 + H2O CH4 + 2O2  CO2 + 2H2O

Fe + Cl2  FeCl3 2Fe + 3Cl2  2FeCl3

C6H14 + O2  CO2 + H2O 2C6H14 + 19O2  12CO2 + 14 H2O

Al4C3 + H2O  CH4 + Al(OH)3 Al4C3 + 12H2O  3CH4 + 4Al(OH)3

Balance the following chemical equations. ___ Ca + ____ H2O  ____Ca(OH)2+____H2 Ca + 2 H2O  Ca(OH)2 + H2 2. ____Cu2S + _____O2  ____Cu2O + ______SO2 2 Cu2S + 3 O2  2 Cu2O + 2SO2 3. _____MnO2 + _____HCl  ______MnCl2 + ______H2O + _____Cl2 MnO2 + 4 HCl  MnCl2 + 2H2O + Cl2 4. _____NH4NO3 + _____NaOH  _____NH3 + _____H2O + _____NaNO3 NH4NO3 + NaOH  NH3 + H2O + NaNO3

3 Zn(OH)2 + 2 H3PO4  Zn3(PO4)2 + 6H2O 3 CO + Fe2O3  2 Fe + 3 CO2 5. ____Fe(OH)3  _____Fe2O3 + _____H2O 2Fe(OH)3  Fe2O3 + 3H2O 6. _____C3H6 + _____O2  _____CO2 + _____H2O 2C3H6 + 9O2  6CO2 + 6H2O 7. __Zn(OH)2 + __H3PO4  __Zn3(PO4)2 + ___H2O 3 Zn(OH)2 + 2 H3PO4  Zn3(PO4)2 + 6H2O 8. _____CO + _____Fe2O3  _____Fe + _____CO2 3 CO + Fe2O3  2 Fe + 3 CO2 _ NH4Cl + __Ca(OH)2  ___NH3 + ___H2O + __CaCl2 2NH4Cl + Ca(OH)2  2 NH3 + 2 H2O + CaCl2 ___HC2H3O2 + ___NaHCO3  __CO2 + __NaC2H3O2 + __H2O HC2H3O2 + NaHCO3  CO2 + NaC2H3O2 + H2O

Write a balanced chemical equation for each of the following reactions Write a balanced chemical equation for each of the following reactions. Include physical state symbols. 1. Copper metal heated with oxygen gives solid copper(II) oxide. 2Cu(s) + O2(g)  2CuO(s)

2. Mixing ammonium nitrate and sodium hydroxide solutions gives aqueous sodium nitrate, ammonia gas, and water. NH4NO3(aq) + NaOH(aq)  NaNO3(aq) + NH3(g) + H2O(l)

3. Mercury(II) nitrate solution reacts with potassium iodide solution to give a mercury(II) iodide precipitate and potassium nitrate solution. Hg(NO3)2(aq) + 2KI(aq)  HgI2(s) + 2KNO3(aq)

4. Solutions of acetic acid and lithium hydroxide produce water and aqueous lithium acetate. HC2H3O2(aq) + LiOH(aq)  H2O(l) + LiC2H3O2(aq)

5. Heating solid potassium chlorate in the presence of manganese dioxide catalyst produced potassium chloride and oxygen gas. 2KClO3(s) MnO2 2KCl(s) + 3O2(g)

DECOMPOSITION REACTIONS -Reaction where a compound breaks down into two or more elements or compounds. Heat, electrolysis, or a catalyst is usually necessary.

A compound may break down to produce two elements. Ex. Molten sodium chloride is electrolyzed. 2NaCl 2Na + Cl2

A compound may break down to produce an element and a compound. Ex. A solution of hydrogen peroxide is decomposed catalytically. 2H2O2  2H2O + O2

A compound may break down to produce two compounds. Ex. Solid magnesium carbonate is heated. MgCO3 MgO + CO2

Metallic carbonates break down to yield metallic oxides and carbon dioxide. K2CO3  K2O + CO2

Metallic chlorates break down to yield metallic chlorides and oxygen. 2RbClO3  2RbCl + 3O2

Metallic sulfites break down to yield metallic oxides and sulfur dioxide. BaSO3  BaO + SO2

Hydrogen peroxide decomposes into water and oxygen.

Sulfurous acid decomposes into water and sulfur dioxide.

Carbonic acid decomposes into water and carbon dioxide.

Hydrated salts decompose into the salt and water Sodium carbonate monohydrate is heated. Na2CO3.H2O Δ Na2CO3 + H2O

Complete and balance the following reactions:

1. ZnCO3  ZnCO3  ZnO + CO2

2. KClO3  2KClO3 2KCl + 3O2

3. HgO  2HgO 2Hg + O2

4. H2CO3  H2CO3 H2O + CO2

2NaCl electricity > 2Na + Cl2

6. H2SO3  H2SO3 H2O + SO2

7. CaCO3 CaCO3CaO + CO2

2H2O electricity > 2H2 + O2

9. Na2SO4.10H2O  Na2SO4.10H2O  Na2SO4 +10H2O

10. H2O2 MnO2 > 2H2O2 MnO2 >2H2O + O2

11. CuSO4.5H2O  CuSO4.5H2O  CuSO4 + 5H2O

ADDITION REACTIONS -also called synthesis, combination or composition reactions -Two or more elements or compounds combine to form a single product.

-A Group IA or IIA metal may combine with a nonmetal to make a salt. Ex. A piece of lithium metal is dropped into a container of nitrogen gas. 6Li + N2  2Li3N

-Two nonmetals may combine to form a molecular compound. C + O2  CO2

-Two compounds combine to form a single product. Sulfur dioxide gas is passed over solid calcium oxide. SO2 + CaO  CaSO3

-A metallic oxide plus carbon dioxide yields a metallic carbonate -A metallic oxide plus carbon dioxide yields a metallic carbonate. (Carbon keeps the same oxidation state) Li2O + CO2  Li2CO3

-A metallic oxide plus sulfur dioxide yields a metallic sulfite -A metallic oxide plus sulfur dioxide yields a metallic sulfite. (Sulfur keeps the same oxidation state) K2O + SO2  K2SO3

-A metallic oxide plus water yields a metallic hydroxide -A metallic oxide plus water yields a metallic hydroxide. CaO + H2O Ca(OH)2

-A nonmetallic oxide plus water yields an acid. CO2 + H2O  H2CO3

Complete and balance the following equations:

1. Li + I2  2Li + I2  2LiI

2. Mg + N2  3Mg + N2  Mg3N2

3. SO3 + H2O  SO3 + H2O  H2SO4

4. Sr + S  Sr + S  SrS

5. Mg + O2  2Mg + O2  2MgO

6. Ag + O2  4Ag + O2  2Ag2O

7. Na2O + H2O  Na2O + H2O  2NaOH

8. SO2 + H2O  SO2 + H2O H2SO3

9. BaO + CO2 BaO + CO2 BaCO3

10. CaO + SO2  CaO + SO2  CaSO3

Double Replacement (metathesis) Two compounds react to form two new compounds. All double replacement reactions must have a "driving force" that removes a pair of ions from solution. Ions keep their same charges as reactants and products.

Formation of a precipitate: A precipitate is an insoluble substance formed by the reaction of two aqueous substances. Two ions bond together so strongly that water can not pull them apart.

SOLUBILITY SONG Nitrates and Group One and Ammonium, To the tune of “ My Favorite Things” from “The Sound of Music” Nitrates and Group One and Ammonium, These are all soluble, a rule of thumb. Then you have chlorides, they’re soluble fun, All except Silver, Lead, Mercury I. Then you have sulfates, except for these three: Barium, Calcium and Lead, you see. Worry not only few left to go still. We will do fine on this test. Yes, we will! Then you have the--- Insolubles Hydroxide, Sulfide and Carbonate and Phosphate, And all of these can be dried!

Ex. Solutions of silver nitrate and lithium bromide are mixed. AgNO3(aq) + LiBr(aq) AgBr(s) + LiNO3(aq)

Formation of a gas: Gases may form directly in a double replacement reaction or can form from the decomposition of a product such as H2CO3 or H2SO3. (Don't leave carbonic or sulfurous acids, or ammonium hydroxide as products of double replacement reactions, decompose them!)

2HCl(aq) + K2SO3(aq) 2KCl(aq) + H2O(l) + SO2(g) Ex. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 2HCl(aq) + K2SO3(aq) 2KCl(aq) + H2O(l) + SO2(g)

NaOH(aq)+ NH4Cl(aq)  NH3(g) + H2O(l) + NaCl(aq) Ex. A solution of sodium hydroxide is added to a solution of ammonium chloride. NaOH(aq)+ NH4Cl(aq)  NH3(g) + H2O(l) + NaCl(aq)

Formation of a molecular substance: When a molecular substance such as water or acetic acid is formed, ions are removed from solution and the reaction "works".

LiOH(aq) + HBr(aq)  LiBr(aq) + H2O Ex. Dilute solutions of lithium hydroxide and hydrobromic acid are mixed. LiOH(aq) + HBr(aq)  LiBr(aq) + H2O

Complete and balance the following equations:

2NaOH + CuSO4  Na2SO4 + Cu(OH)2(s)

NH4I + AgNO3  NH4NO3 + AgI(s)

K2CO3 + Ba(OH)2  2KOH + BaCO3(s)

4. KOH + HI KOH + HIKI + H2O(l)

5. K2CO3 + HNO3  K2CO3 + 2HNO3  2KNO3 + H2O + CO2

(NH4)2SO4 + BaCl2  2NH4Cl + BaSO4(s)

Na2S + NiSO4  NiS(s) + Na2SO4

Pb(NO3)2 + 2KBr  PbBr2(s) + 2KNO3

Fe2(SO4)3 + 3Ba(OH)2  2Fe(OH)3(s) + 3BaSO4(s)

Hg2(NO3)2 + 2KI  2KNO3 + Hg2I2(s)

Single Replacement Reaction where one element displaces another in a compound. One element is oxidized and another is reduced. A + BC  B + AC

Active metals replace less active metals or hydrogen from their compounds in aqueous solution. Use an activity series to determine the activity of metal.

Ex. Magnesium turnings are added to a solution of iron(III) chloride. 3Mg(s) + 2FeCl3(aq)  2Fe(s) + 3MgCl2(aq)

Ex. Sodium is added to water. 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) Reactions of Alkali metals

Ex. Fe + H2O Fe + H2O no reaction

Active nonmetals replace less active nonmetals from their compounds in aqueous solution. Each halogen will displace heavier halogens from their binary salts.

Activity Series of Nonmetals Most Active F2 Cl2 Br2 Least Active I2

Ex. Chlorine gas is bubbled into a solution of potassium iodide. Cl2(g) + 2KI(aq)  I2(s) + 2KCl(aq)

Ex. I2 + KCl  I2 + KCl  no reaction

Complete and balance the following equations:

1. Zn + HCl  Zn +2 HCl ZnCl2 + H2

2. Br2 + NaCl  Br2 + NaCl  No Reaction

3. F2 + NaBr  F2 + 2NaBr 2NaF + Br2

4. Al + CuSO4  2Al + 3CuSO4  Al2(SO4)3 + 3Cu

5. Cu + AgNO3  Cu + 2AgNO3  Cu(NO3)2 + 2Ag

6. Cd + CuSO4  Cd + CuSO4  CdSO4 + Cu

7. K + H2O  2K + 2H2O  2KOH + H2

8. Mg + H2SO4  Mg + H2SO4  MgSO4 + H2

9. Ag + HCl  Ag + HCl No Rxn

10. I2 + KCl  I2 + KCl No Rxn

11. Ca + H2O  Ca + 2H2O Ca(OH)2 + H2

12. Zn + H2O  Zn + H2O No Rxn

COMBUSTION REACTIONS

In the presence of excess oxygen, most hydrocarbons and alcohols can undergo complete combustion reactions to form carbon dioxide and water. The only tricky part is balancing the reaction. Balance the C first, H second, and O third.

Ex. Ethane (C2H6) burns in air. 2C2H6 + 7O2  4CO2 + 6H2O

Ethanol (C2H5OH) burns C2H5OH + 3O2  2CO2 + 3H2O

Complete and balance the reactions for the combustion of the following compounds:

1. CH4 CH4 + 2O2  CO2 + 2H2O

2. C2H2 2C2H2 + 5 O2  4CO2 + 2H2O

3. CH3OH 2CH3OH + 3O2  2CO2 + 4H2O

4. C6H12O6 C6H12O6 + 6O2  6CO2 + 6H2O

5. C8H18 2C8H18 + 25O2  16CO2 + 18H2O

6. C3H8 C3H8 + 5O2  3CO2 + 4H2O

7. C6H6 2C6H6 + 15O2  12CO2 + 6H2O

8. C2H4 C2H4 + 3O2  2CO2 + 2H2O

9. C35H72 C35H72 + 53O2  35CO2 +36 H2O

10. C3H7OH 2C3H7OH + 9O2  6CO2 + 8H2O

SYNTHESIS AND DECOMPOSITION REACTIONS

Complete and balance the following equations:

1. Sr + O2  2Sr + O2 2SrO

2. Na + O2  4Na + O2 2Na2O

3. K + Cl2  2K + Cl2 2KCl

4. Ca + F2  Ca + F2 CaF2

5. sodium + iodine  2Na + I2 2NaI

6. magnesium + oxygen  2Mg + O2 2MgO

7. hydrogen + chlorine  H2 + Cl2  2HCl

8. silver + sulfur  2Ag + S  Ag2S

9. calcium oxide + water  CaO + H2O  Ca(OH)2

10. sulfur trioxide + water  SO3 + H2O  H2SO4

11. MgBr2 MgBr2 Mg + Br2

12. AlCl3  2AlCl3 2Al + 3Cl2

13. H2O  2H2O 2H2 + O2

14. KI  2KI 2K + I2

15. NaCl  2NaCl 2Na + Cl2

16. nickel(II) chlorate  Ni(ClO3)2  NiCl2 + 3O2

SINGLE AND DOUBLE REPLACEMENT REACTIONS

Write and balance the following reactions:

Zn(s) + CuSO4(aq) ZnSO4(aq) + Cu(s)

Cl2(g) + 2KI(aq) 2KCl(aq) + I2(s)

Ni(s) + MgSO4(aq) No Reaction

Br2(l) + CaCl2(aq) No Rxn

5. zinc + copper(II) nitrate  Zn(s) + Cu(NO3)2(aq)  Cu(s) + Zn(NO3)2(aq)

6. calcium + hydrochloric acid  Ca(s) + 2HCl(aq)  CaCl2(aq) + H2(g)

7. copper(II) nitrate + silver  Cu(NO3)2(aq) + Ag(s)  No Rxn

8. sodium iodide + bromine  2NaI(aq) + Br2(l)  2NaBr(aq) + I2(s)

2Na(s) + 2H2O(l)  2NaOH(aq) + H2(g) 9. sodium + water  2Na(s) + 2H2O(l)  2NaOH(aq) + H2(g)

FeCl2(aq) + K2S(aq)  FeS(s) + 2KCl(aq) 10. FeCl2 + K2S  FeCl2(aq) + K2S(aq)  FeS(s) + 2KCl(aq)

ZnCl2(aq) + Pb(NO3)2(aq) Zn(NO3)2(aq) + PbCl2(s) 11. ZnCl2 + Pb(NO3)2  ZnCl2(aq) + Pb(NO3)2(aq) Zn(NO3)2(aq) + PbCl2(s)

CaCl2(aq) + Na2CO3(aq)  2NaCl(aq) + CaCO3(s) 12. CaCl2 + Na2CO3  CaCl2(aq) + Na2CO3(aq)  2NaCl(aq) + CaCO3(s)

(NH4)2SO4(aq) + BaCl2(aq)  2NH4Cl(aq) + BaSO4(s) 13. (NH4)2SO4 + BaCl2  (NH4)2SO4(aq) + BaCl2(aq)  2NH4Cl(aq) + BaSO4(s)

14. sodium hydroxide + acetic acid  NaOH(aq) + HC2H3O2(aq)  NaC2H3O2(aq) + H2O(l)

15. copper(II) sulfate + ammonium sulfide  CuSO4(aq) + (NH4)2S(aq)  CuS(s) + (NH4)2SO4(aq)

MIXED EQUATION WORKSHEET #1 Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

1. Magnesium hydroxide + nitric acid  magnesium nitrate + water Mg(OH)2 + 2HNO3  Mg(NO3)2 + 2H2O DR

2. Complete combustion of methane (CH4) methane + oxygen  carbon dioxide + water CH4 + 2O2  CO2 + 2H2O Combustion

3. Chlorine + sodium bromide  bromine + sodium chloride Cl2 + 2NaBr  Br2 + 2NaCl Single Replacement

4. Aluminum + sulfuric acid  aluminum sulfate + hydrogen 2Al + 3H2SO4 Al2(SO4)3 + 3H2 Single replacement

5. Sulfuric acid + sodium acetate  sodium sulfate + acetic acid H2SO4 + 2NaC2H3O2  Na2SO4 + 2HC2H3O2 Double replacement

6. Heating calcium carbonate  calcium oxide + carbon dioxide CaCO3  CaO + CO2 Decomposition

7. Heating mercuric oxide  mercury + oxygen 2HgO  2Hg + O2 Decomposition

8. Zinc + silver nitrate  Zinc + silver nitrate  zinc nitrate + silver Zn + 2AgNO3  Zn(NO3)2 + 2Ag Single Replacement

Sulfur + oxygen  sulfur dioxide S + O2  SO2 synthesis 9. Burning sulfur Sulfur + oxygen  sulfur dioxide S + O2  SO2 synthesis

10. Heating sodium chlorate sodium chloride + oxygen 2NaClO3  2NaCl + 3O2 Decomposition

11. Zinc chloride + ammonium sulfide  zinc sulfide + ammonium chloride ZnCl2 + (NH4)2S  ZnS + 2NH4Cl double replacement

12. Aluminum hydroxide + hydrochloric acid  Aluminum hydroxide + hydrochloric acid  aluminum chloride + water Al(OH)3 + 3HCl  AlCl3 + 3H2O Double replacement

13. Calcium + steam  Calcium + steam  calcium hydroxide + hydrogen Ca + 2H2O  Ca(OH)2 + H2 Single replacement

carbonic acid  water + carbon dioxide H2CO3  H2O + CO2 Decomposition 14. Heating carbonic acid carbonic acid  water + carbon dioxide H2CO3  H2O + CO2 Decomposition

15. Electrolysis of sodium chloride  sodium + chlorine 2NaCl  2Na + Cl2 Decomposition

16. Combustion of propane (C3H8) Propane + oxygen  Carbon dioxide + water C3H8 + 5O2  3CO2 +4 H2O Combustion

17. Bromine + potassium iodide  Iodine + potassium bromide Br2 + 2KI  I2 + 2KBr Single Replacement

18. Magnesium + hydrochloric acid  magnesium chloride + hydrogen Mg + 2HCl  MgCl2 + H2 Single replacement

19. Sodium hydroxide + acetic acid  sodium acetate + water NaOH + HC2H3O2  NaC2H3O2 + H2O Double replacement

20. Burning hydrogen  hydrogen + oxygen  water 2H2 + O2  2H2O Synthesis or combustion

zinc sulfate + hydrogen Zn + H2SO4  ZnSO4 + H2 single replacement 21. Zinc + sulfuric acid  Zinc + sulfuric acid  zinc sulfate + hydrogen Zn + H2SO4  ZnSO4 + H2 single replacement

22. Heating magnesium carbonate magnesium oxide + carbon dioxide MgCO3  MgO + CO2 Decomposition

Sodium + chlorine  sodium chloride 2Na + Cl2  2NaCl Synthesis

24. Lead(II) nitrate + sodium iodide  lead (II) iodide + sodium nitrate Pb(NO3)2 + 2NaI  PbI2 + 2NaNO3 Double replacement

25. Silver nitrate + sodium sulfide  silver sulfide + sodium nitrate 2AgNO3 + Na2S  Ag2S + 2NaNO3 Double replacement

26. Iodine + potassium chloride  No Reaction

27. Magnesium oxide + water  magnesium hydroxide MgO + H2O  Mg(OH)2 synthesis

MIXED EQUATION WORKSHEET #2

Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

1. sodium hydrogen carbonate + hydrochloric acid  sodium hydrogen carbonate + hydrochloric acid  sodium chloride + water + carbon dioxide NaHCO3 + HCl  NaCl + H2O + CO2 double replacement

2. Complete combustion of ethanol (C2H5OH) Ethanol + oxygen  carbon dioxide + water C2H5OH + 3O2  2CO2 + 3H2O Combustion

3. sulfurous acid + magnesium hydroxide  water + magnesium sulfite H2SO3 + Mg(OH)2  2H2O + MgSO3 double replacement

4. carbonic acid + lithium hydroxide  water + lithium carbonate H2CO3 + 2LiOH  2H2O + Li2CO3 Double replacement

5. gold + sulfuric acid  gold + sulfuric acid  No Reaction

6. aluminum + fluorine  aluminum + fluorine  aluminum fluoride 2Al + 3F2  2AlF3 Synthesis

7. calcium oxide + water  calcium oxide + water  calcium hydroxide CaO + H2O  Ca(OH)2 Synthesis

8. acetic acid + sodium hydroxide  water + sodium acetate HC2H3O2 + NaOH  H2O +NaC2H3O2 Double replacement

9. potassium chloride + lead(II) nitrate  potassium nitrate + lead(II) chloride 2KCl + Pb(NO3)2  2KNO3 + PbCl2 Double replacement

10. carbon monoxide + oxygen  carbon dioxide 2CO + O2  2CO2 Synthesis

sodium + chlorine  sodium chloride 2Na + Cl2  2NaCl Synthesis

12. dinitrogen pentoxide + water  nitric acid N2O5 + H2O  H2N2O6 2HNO3 Synthesis

13. bromine + sodium chloride  No rxn

14. potassium chloride + mercury(I) nitrate potassium nitrate + mercury(I) chloride 2KCl + Hg2(NO3)2  2KNO3 + Hg2Cl2 Double replacement

15. sulfur dioxide + water  sulfurous acid SO2 + H2O  H2SO3 Synthesis

lithium oxide + water  lithium hydroxide Li2O + H2O  2LiOH Synthesis

17. heating zinc carbonate zinc oxide + carbon dioxide ZnCO3  ZnO + CO2 Decomposition

18. silver nitrate + sodium chloride  silver chloride + sodium nitrate AgNO3 + NaCl  AgCl + NaNO3 Double replacement

19. heating beryllium chlorate beryllium chloride + oxygen Be(ClO3)2  BeCl2 + 3O2 Decomposition

20. electrolysis of water water hydrogen + oxygen 2H2O  2H2 + O2 Decomposition

21. complete combustion of butane (C4H10) Butane + oxygen  carbon dioxide + water 2C4H10 + 13O2  8CO2 + 10H2O Combustion

22. iron(II) sulfate + ammonium sulfide  iron(II) sulfide + ammonium sulfate FeSO4 + (NH4)2S  FeS + (NH4)2SO4 Double replacement

23. lithium + water lithium + water lithium hydroxide + hydrogen 2Li + 2H2O  2LiOH + H2 Single replacement

24. potassium oxide + water potassium hydroxide K2O + H2O  2KOH Synthesis

25. silver + sulfur silver + sulfur silver sulfide 2Ag + S  Ag2S Synthesis

26. sodium + water sodium + water sodium hydroxide + hydrogen 2Na + 2H2O  2NaOH + H2 Single replacement

27. calcium hydroxide + ammonium sulfate calcium sulfate + ammonia + water Ca(OH)2 + (NH4)2SO4  CaSO4 + 2NH3 + 2H2O Double replacement

NET IONIC EQUATIONS

Net ionic equations show only the species actually involved in the reaction. As you first learn to write net ionic equations, you will write three different equations for each reaction.

Steps in writing net ionic equations:

1. Write the complete molecular equation 1. Write the complete molecular equation. (This is the type of equation that you are accustomed to writing.)

2. Write the complete ionic equation 2. Write the complete ionic equation. To do this, you must ionize everything that is soluble and ionized in solution. Everything else is left together. Do not ionize solids, gases or weak electrolytes.

3. Write the net ionic equation 3. Write the net ionic equation. To do this, cancel out all ions that are not participating in the reaction (spectator ions) and rewrite the equation.

Sodium chloride + silver nitrate 1. NaCl(aq) + AgNO3(aq)  NaNO3(aq) + AgCl(s) 2. Na+ + Cl- + Ag+ + NO3-  Na+ + NO3- + AgCl(s) 3. Cl- + Ag+ AgCl

Ex. HCl + Ba(OH)2  1. 2HCl + Ba(OH)2  2H2O + BaCl2 3. 2H+ + 2OH-  2H2O H+ + OH-  H2O

Write net ionic equations for the following reactions:

1. KCl(aq) + Pb(NO3)2(aq) 2KCl(aq) + Pb(NO3)2(aq) 2KNO3(aq) + PbCl2(s) 2K+ + 2Cl- + Pb2+ + 2NO3-  2K+ + 2NO3- + PbCl2 Pb2+ + 2Cl-  PbCl2

2. HCl(aq) + CaSO3(s) 2HCl(aq) + CaSO3(s) H2O(l) + SO2(g) + CaCl2(aq) 2H+ + 2Cl- + CaSO3  H2O + SO2 + Ca2+ + 2Cl- 2H+ + CaSO3  H2O + SO2 + Ca2+

3. Zn(s) + O2(g)  2Zn(s) + O2(g) 2ZnO(s)

4. Li(s) + H2O(l)  2Li(s) + 2H2O(l)  2LiOH(aq) + H2(g)

5. Na2SO4(aq) + BaBr2(aq) Na2SO4(aq) + BaBr2(aq) 2NaBr(aq) + BaSO4(s) 2Na+ + SO42- + Ba2+ + 2Br-  2Na+ + 2Br- + BaSO4 SO42- + Ba2+  BaSO4

6. MgCO3(s) MgCO3(s) MgO(s) + CO2(g)

7. AgNO3(aq) + Na2CO3(aq)  2AgNO3(aq) + Na2CO3(aq)  Ag2CO3(s) + 2NaNO3(aq) 2Ag+ + 2NO3- + 2Na+ + CO32-  Ag2CO3 + 2Na+ + 2NO3- 2Ag+ + CO32-  Ag2CO3

8. Na2S(aq) + HCl(aq)  Na2S(aq) + 2HCl(aq)  2NaCl(aq) + H2S(g) 2Na+ + S2- + 2H+ + 2Cl-  2Na+ + 2Cl- + H2S S2- + 2H+  H2S

9. H2SO3(aq)  H2SO3(aq) H2O(l) + SO2(g)

10. Cl2(g) + NaI(aq)  Cl2(g) + 2NaI(aq) I2(s) + 2NaCl(aq) Cl2 + 2Na+ + 2I- I2 + 2Na+ + 2Cl- Cl2 + 2I- I2 + 2Cl-

EXTRA EQUATION WORKSHEET PRE-AP CHEMISTRY

Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

1. heating magnesium carbonate magnesium oxide + carbon dioxide MgCO3  MgO + CO2 Decomposition

2. complete combustion of propanol (C3H7OH) propanol + oxygen  carbon dioxide + water 2C3H7OH + 9O2  6CO2 + 8H2O Combustion

S + O2  SO2 Synthesis 3. sulfur + oxygen  sulfur + oxygen sulfur dioxide S + O2  SO2 Synthesis

4. sulfuric acid + cadmium  cadmium sulfate + hydrogen H2SO4 + Cd  CdSO4 + H2 Single Replacement

5. sulfur dioxide + water  sulfurous acid SO2 + H2O  H2SO3 Synthesis

6. hydrochloric acid(aq) + calcium carbonate(s)  carbon dioxide(g) + water(l) + calcium chloride(aq) 2HCl + CaCO3  CO2 + H2O + CaCl2 Double replacement

7. net ionic equation for #6 1. 2HCl(aq) + CaCO3(s)  CO2(g) + H2O(l) + CaCl2(aq) 2. 2H+ + 2Cl- + CaCO3  CO2 + H2O + Ca2+ + 2Cl- 3. 2H+ + CaCO3  CO2 + H2O + Ca2+

8. silver nitrate (aq)+ hydrochloric acid (aq) silver chloride(s) + nitric acid(aq) AgNO3 + HCl  AgCl + HNO3 Double replacement

9. net ionic equation for #8 1. AgNO3(aq) + HCl(aq)  AgCl(s) + HNO3(aq) 2. Ag+ + NO3- + H+ + Cl-  AgCl(s) + H+ + NO3- 3. Ag+ + Cl-  AgCl(s)

10. barium nitrate(aq) + potassium sulfate (aq) barium sulfate(s) + potassium nitrate(aq) Ba(NO3)2 + K2SO4  BaSO4 + 2KNO3 Double Replacement

11. net ionic equation for #10 1. Ba(NO3)2 (aq) + K2SO4(aq)  BaSO4(s) + 2KNO3(aq) 2. Ba2+ + 2NO3- + 2K+ + SO42-  BaSO4 + 2K+ + 2NO3- 3. Ba2+ + SO42-  BaSO4

12. sodium hydroxide + phosphoric acid  sodium phosphate + water 3NaOH + H3PO4  Na3PO4 + 3H2O Double replacement

13. iodine + rubidium chloride  iodine + rubidium chloride  No Rxn

14. magnesium(s) + copper(II) sulfate(aq) magnesium sulfate(aq) + copper(s) Mg + CuSO4  MgSO4 + Cu Single replacement

15. net ionic equation for #14 1. Mg(s) + CuSO4(aq)  MgSO4(aq) + Cu(s) 2. Mg + Cu2+ + SO42-  Mg2+ +SO42- + Cu 3. Mg + Cu2+  Mg2+ + Cu

16. ammonium nitrate(aq) + sodium hydroxide(aq)  ammonium nitrate(aq) + sodium hydroxide(aq)  ammonia (g)+ water (l) + sodium nitrate (aq) NH4NO3 + NaOH  NH3 + H2O + NaNO3 Double replacement

17. net ionic equation for #16 1. NH4NO3(aq) + NaOH(aq)  NH3(g) + H2O(l) + NaNO3(aq) 2. NH4+ + NO3- + Na+ + OH-  NH3 + H2O + Na+ + NO3- 3. NH4+ + OH-  NH3 + H2O

18. potassium(s) + water(l)  potassium hydroxide(aq) + hydrogen(g) 2K + 2H2O  2KOH + H2 Single Replacement

19. net ionic equation for #18 1. 2K(s) + 2H2O(l)  2KOH(aq) + H2(g) 2. 2K + 2H2O  2K+ + 2OH- + H2

20. sodium bromide(aq) + chlorine(g) sodium chloride + bromine 2NaBr + Cl2  2NaCl + Br2 Single replacement

21. net ionic equation for #20 1. 2NaBr(aq) + Cl2(g)  2NaCl(aq) + Br2(l) 2. 2Na+ + 2Br- + Cl2  2Na+ + 2Cl- + Br2 3. 2Br- + Cl2  2Cl- + Br2

aluminum + nitrogen aluminum nitride 2Al + N2  2AlN Synthesis

23. sodium sulfide(aq) + hydrochloric acid(aq) sodium sulfide(aq) + hydrochloric acid(aq) sodium chloride (aq) + hydrogen sulfide (g) Na2S + 2HCl  2NaCl + H2S Double replacement

24. net ionic equation for #23 1. Na2S(aq) + 2HCl(aq)  2NaCl(aq) + H2S(g) 2. 2Na+ + S2-+ 2H+ + 2Cl-  2Na+ + 2Cl-+ H2S 3. S2-+ 2H+  H2S

25. heating magnesium sulfate heptahydrate magnesium sulfate + water MgSO4.7H2O  MgSO4 + 7H2O Decomposition

26. heating mercury(II) oxide mercury + oxygen 2HgO  2Hg + O2 Decomposition

27. bromine + strontium chloride bromine + strontium chloride No Rxn

1. Dilute hydrochloric acid is added to a solution of potassium sulfite. 2HCl(aq) +K2SO3(aq) H2O(l) + SO2(g) +2KCl(aq) 2H+ + 2Cl- +2K+ + SO32- H2O(l) + SO2(g) +2K+ +2Cl- 2H+ + SO32- H2O(l) + SO2(g)

2. A solution of sodium sulfide is added to a solution of zinc nitrate. Na2S(aq) + Zn(NO3)2(aq)  2NaNO3(aq) + ZnS(s) 2Na+ + S2- + Zn2+ + 2NO3-  2Na+ + 2NO3- + ZnS S2- + Zn2+  ZnS

3. Chlorine gas is bubbled into a solution of potassium iodide. Cl2(g) + 2KI(aq)  2KCl(aq) + I2(s) Cl2 + 2K+ + 2I-  2K+ + 2Cl- + I2 Cl2 + 2I- -> 2Cl- + I2

4. Magnesium metal is burned in nitrogen gas. 3Mg(s) + N2(g)  Mg3N2(s)

5. Solid sodium oxide is added to water. Na2O(s) + H2O(l)  2NaOH(aq) Na2O(s) + H2O(l) 2Na+(aq) + 2OH-(aq)