Chapter 7
This presentation is the property of its rightful owner.
Sponsored Links
1 / 24

Chapter 7 PowerPoint PPT Presentation


  • 69 Views
  • Uploaded on
  • Presentation posted in: General

Chapter 7. Balancing Chemical Equations. Chemical Reaction. Describes chemical reaction. Chemical equation: reactants yield products. Catalyst = substance that speeds up a reaction without being used up. Symbols Used. (s) solid (l) liquid (g) gas

Download Presentation

Chapter 7

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Chapter 7

Chapter 7

Balancing Chemical Equations


Chemical reaction

Chemical Reaction

  • Describes chemical reaction.

  • Chemical equation: reactants yield products

Catalyst = substance that speeds up a reaction

without being used up.


Symbols used

Symbols Used

  • (s) solid

  • (l) liquid

  • (g) gas

  • (aq) aqueous (in water solution)

  • gas as a product

  • ppt. (precipitate)

  • D means with heat

  • Ptmeans with Platinum catalyst


Balancing chemical equations

Balancing Chemical Equations

  • Balanced equations have: the same # of atoms of each element on each side of the equation.

  • Law of Conservation of Mass – atoms can neither be created nor destroyed, simply rearranged.


Rules for balancing equations

Rules for Balancing Equations

  • Get the correct formulas for reactants and products.

  • Write reactants on left, products on right and use plus signs and arrows when needed.

  • Count the # of atoms of each element in reactants and products.(Polyatomic ions on both sides count as one.)

  • Balance # of each element using coefficients.

    • Coefficient – whole # in front of a formula.


Rules for balancing equations1

Rules for Balancing Equations

  • Check each element to make sure equation is balanced.

  • Make sure all coefficients are in the lowest whole number ratio.

Do not change subscripts!!!


Diatomic molecules

Diatomic Molecules

Diatomic Molecules- a molecule made up two atoms of the same element. They are only diatomic when they are alone.

  • There are 7 naturally occurring

  • diatomic molecules.

HONClBrIF


5 types of reactions 1

5 Types of Reactions - 1

Combination Reaction – elements combine to form a compound.

A + B AB


Examples of combination reactions

Examples of Combination Reactions

1. 2 Na + Cl2 2 NaCl

2

2. Cu + S Cu2S

3. SO3 + H2O

H2SO4

4. CaO + H2O

Ca(OH)2

2

MgO

5. Mg + O2

2


5 types of reactions 2

5 Types of Reactions - 2

Decomposition Reaction – elements break down into its element.

AB A + B


Examples of decomposition reactions

Examples of Decomposition Reactions

1. 2 NaCl 2 Na + Cl2

2

2

2. H2O H2 + O2

2

3. HgO

2

Hg +O2

Challenge: Copper I Chloride Decomposes

2CuCl 2Cu + Cl2


5 types of reactions 3

5 Types of Reactions - 3

Single Replacement Reaction – one element replaces another element in a compound.

AB + C A + CB

or

AB + D AD + B

+ - + + + -

+ - - + - -


Reactivity series of metals and non metals

Reactivity Series of Metals and Non-Metals

  • The single metallic element will only replace the metal in a compound if it is more reactive.

  • A chart is used to determine if the lone metal is more reactive. If not, no reaction occurs.

  • The single non-metallic element will only replace the non-metal in a compound if it is more reactive. The higher up in the group the non-metal is, the more reactive it is.


Examples of single replacement reactions

Examples of Single Replacement Reactions

1. Zn + H2SO4 ZnSO4 + H2

2. K + HOH KOH + H2

2

2

NaCl + Br2

3. Cl2 + NaBr


5 types of reactions 4

5 Types of Reactions - 4

Double Replacement Reaction – two compounds react and exchange positive ions to form two new compounds.

AB + CD AD + CB

+ - + - + - + -


Examples of double replacement reactions

Examples of Double Replacement Reactions

1. NaOH + H2SO4 Na2SO4 + HOH

2

2

2. BaCl2 + K2CO3 BaCO3 + KCl

2

3. FeS + HCl

2

H2S + FeCl2


5 types of reactions 5

5 Types of Reactions - 5

Combustion Reaction – oxygen reacts with a compound composed of C and H.

CxHy + O2 CO2 + H20

Also called Burning (exothermic)

The products are always CO2 and H2O.


Examples of combustion reactions

Examples of Combustion Reactions

1. C6H6 + O2 CO2 + H2O

6

3

2 15 12 6

C6H6 + O2 CO2 + H2O

2. CH3OH + O2 CO2 + H2O

2

2 3 2 4

CH3OH + O2 CO2 + H2O


Special decomposition reactions 1

Special Decomposition Reactions: 1

  • Decomposition of a Carbonate:

    XCO3 XO + CO2

ex. Na2CO3 Na2O + CO2


Special decomposition reactions 2

Special Decomposition Reactions: 2

  • Decomposition of a Hydroxide:

    XOH XO + H2O

ex. 2NaOH Na2O + H2O


Special decomposition reactions 3

Special Decomposition Reactions: 3

  • Decomposition of a Chlorate:

    XClO3 XCl + O2

ex. NaClO3 NaCl + O2


Special decomposition reactions 4

Special Decomposition Reactions: 4

  • Special single Replacement Reaction:

    • Group IA or IIA metal and H2O

      X + HOH XOH + H2

ex. 2Na + 2HOH 2NaOH + H2


How to id types of reactions

How to ID types of reactions.

Combination Reactions – given 2 items that form 1 new compound.

Decomposition Reactions – given a single compound that breaks into parts.

Single Replacement – given a single elementplus a single compound, forms a new compound a a different element.

Double Replacement – given two compounds (+’s or –’s change places).

Combustion Reaction – given CH compound with Oxygen, always forms water and carbon dioxide.


Chapter 7

The End


  • Login