Review of Ionic and Review of Ionic and Molecular Formula Molecular Formula Writing:Writing:

Chapter 8 Outline

8.1 – Chemical Equations

The symbols and formulas used to represent reactants

and products

Reading and Writing Chemical Equations:

1. Represent the Facts

2. Use correct formulas for compounds

-Ionic – SWAPPING

-Molecular – PREFIXES

-Diatomics – AUTOMATICALLY get a subscript “2”

Diatomics:

Silly Phrase:HairyNinjasOftenFightCleanBrightItalians

Reading and Writing Chemical Equations:

Metals are the symbol only:

Magnesium metal = Mg

Copper metal = Cu

**No numbers or charges!!*

Reading and Writing Chemical Equations:

3. Law of Conservation of Mass:

Nature balances the reactions, so we must too! We will use COEFFICIENTS which match what nature does.

Types of Equations

Word Equation

-Shows reactants and products in WORDS

-For now these will be given to you

Example:

Methane Gas + Oxygen Gas -> Carbon dioxide + Water

Types of Equations

Formula Equation

-Uses Formulas

Example:

CH4 + O2 -> CO2 + H2O

Types of Equations

Balanced Equation

-Number of each atom on the left matches the number on the right

-THIS IS WHAT NATURE DOES!

Example:

CH4 + 2O2 -> CO2 + 2H2O

Other Symbols

s=solid

l=liquid

g=gas

aq=aqueous=dissolved in water

Reversible Reaction

Add Heat

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Significance of an Equation

-Will give us information about the amounts of reactants and products

-That’s Chapter 9!

Reversible Reactions – Can proceed in either direction.

Balancing Reactions

• Most can be done by inspection

• STEPS1. Write the WORD EQUATION (for now given)

Ex. Water -> Hydrogen Gas + Oxygen Gas(this is called the Electrolysis of Water)

2. Replace words with formulas

Water -> Hydrogen Gas + Oxygen Gas

H2O -> H2+

O2

3. Balancing

-Balance one atom at a time

-Start with elements that are on each side one time only

-Balance polyatomics (like NO3) as an entire group when possible

-Balance O and H last

Water -> Hydrogen Gas + Oxygen Gas

H2O O2-> +H2

H

O

Count atoms to check!

Electrolysis of Water

Practice Problems

More Practice Problems

More Practice Problems

8.2 – Types of Reactions

1. Synthesis

-Combining 2 or more reactants to form one product

A + X -> AX

Example:Magnesium + Oxygen Gas -> Magnesium oxide

8.2 – Types of Reactions2. Decomposition

-Breaking down 1 reactant into 2 or more products

AX -> A + X

Example:

Hydrogen peroxide -> Water + Oxygen gas

8.2 – Types of Reactions

3. Single Displacement

-One element replacing another in a compound

A + BX -> B + AX

-A replaces the one it is most similar to!

Example:aluminum + iron (III) oxide -> iron + aluminum oxide

Single Displacement

Honors must be able to predict products.

Examples:

1.copper (II) nitrate + zinc ->

2.Sodium chloride + fluorine gas ->

8.2 – Types of Reactions

4. Double Displacement

-Two elements switch places in compounds

AX + BY -> AY + BX

Example:Sodium chloride+Silver(I) nitrate->Sodium nitrate+Silver(I) chloride

4 Types of Reactions Review:

(Stop after Dbl Disp)

8.2 – Types of Reactions

4. Double Displacement

-You must be able to predict products for this type of reaction!

Example:

Iron (II) sulfide + Hydrogen chloride ->

Activity Series

• Activity = Ability to react

• Activity Series = List of elements by activity

• High on the list means the element can replace those below it

• Helps us determine whether a reaction will or will not happen

Activity SeriesLiKCaNaMgAlZnFeCoNiSnPbCuHgAg

Most active on this list

Least active on this list

Activity SeriesLiKCaNaMgAlZnCrFeCoNiSnPbCuHgAg

For a single displacement reaction to occur, the SINGLE REACTANT must be HIGHER than the one in the compound

Example: 2Al + 3ZnCl2 -> 3Zn + 2AlCl3

Example: Co + 2NaCl -> CoCl2 + 2Na

Solubility

• Solubility = Ability to dissolve

• Soluble = DissolvesIn Water = Aqueous – aq

• Insoluble = Does NOT DissolveSolid = s = precipitate

SolubilitySolubility Rules (these will be given to you on test):– Group 1 and Ammonium compounds ARE soluble– Acetate, Nitrate, and chlorate compounds ARE

soluble– Group 17 (other than F) ARE soluble EXCEPT

when with Ag, Hg2+2, and Pb– Sulfates ARE soluble EXCEPT when with Ba, Sr,

Pb, Ca, Ag, Hg2+2– Carbonates, Hydroxides, Oxides, Sulfides,

Phosphates, Oxalates are INSOLUBLE**Start at the top and work down. STOP when you hit

the first rule that applies to ANY PART of you compound**

Solubility

Examples:

Cu(NO3)2 =

Silver nitrate + sodium chloride ->