Balancing Chemical Equations - PowerPoint PPT Presentation

1 / 21
About This Presentation
Title:

Balancing Chemical Equations

Description:

Balancing Chemical Equations (hydrogen oxygen -- water) This is a word equation. ... equation. Balancing Chemical Equations ... Balancing Chemical Equations ... – PowerPoint PPT presentation

Number of Views:54
Avg rating:3.0/5.0
Slides: 22
Provided by: des132
Category:

less

Transcript and Presenter's Notes

Title: Balancing Chemical Equations


1
Balancing Chemical Equations
  • (hydrogen oxygen --gt water) This is a word
    equation.
  • What does a word equation tell us?
  • (2H2 O2 --gt2H2O) This is a symbolic equation.

2
Balancing Chemical Equations
  • What does a balanced symbolic tell us? Does it
    tell us more than the word equation?
  • While a word equation tells us certain things, a
    balanced chemical equation tells us much more.

3
Balancing Chemical Equations
  • A BALANCED CHEMICAL EQUATION MUST SATISFY THE LAW
    OF CONSERVATION OF ATOMS. (total number of atoms
    of each element of reactants must equal total
    number of atoms of each element in products.)

4
A Balanced Chemical Equation Tells us the
Following
  • 1. Relative proportions of the reactants and the
    products.
  • 2. Molecule to molecule ratios of all components
    of the reaction.
  • 3. Mole to mole ratios of all components of the
    reaction.

5
A Balanced Chemical Equation Tells us the
Following
  • 4. Mass to mass of each substance in the
    reaction.
  • 5. The ratios of masses of each substance in the
    reaction.
  • 6. The reverse reaction.

6
SYMBOLS
  • Before we start we need to review some symbols
    and abbreviations. ( see page 246 in your text
    book)

7
Factors in Equation Writing
  • 1. The equation must represent the facts.
  • 2. The equation must include all symbols used as
    reactants or products.
  • 3. The law of conservation of atoms must be
    satisfied.

8
SUBSCTRIPTS and COEFFICIENTS
  • Subscripts are the numbers that are behind and
    below the symbol.
  • Coefficients are in front of the symbol.
  • There are different rules for the use of each one
    of these.

9
BrINClHOF
  • Remember that any time we have a BrINClHOF alone
    they require a 2 subscript

10
WRITING BALANCED CHEMICAL EQUATIONS
  • 1. Make sure that the equation represents the
    facts.
  • 2. Write the correct formulas for compounds
    balanced as to oxidation number or charge.
  • 3. Balance according to the law of conservation
    of atoms.

11
EXAMPLES
  • 1. water --gt hydrogen oxygen (remember the
    three steps)
  • 2. Sulfur oxygen --gt sulfur dioxide
  • 3. Mercury II oxide--gt mercury oxygen

12
EXAMPLES CONT.
  • 4. zinc hydrochloric acid ( HCl) --gt zinc
    chloride hydrogen
  • 5. Aluminum sulfate calcium hydroxide --gt
    aluminum hydroxide calcium sulfate

13
5 GENERAL TYPES OF CHEMICAL REACTIONS
  • 1. COMPOSITION
  • A X --gt AX
  • element element --gt compound
  • note there is only one product in this type of
    reaction

14
EXAMPLE
  • 1. Hydrogen oxygen --gt water
  • 2. Iron sulfur --gt iron II sulfide
  • 3. Magnesium oxygen --gt magnesium oxide

15
5 TYPES OF CHEM.RXNS.
  • 2. DECOMPOSITION
  • AX --gt A X
  • compound --gt element element
  • note only one reactant in this type

16
EXAMPLE
  • 1. Water --gt hydrogen oxygen
  • 2. Potassium chlorate --gt potassium chloride
    oxygen (This reaction is different. How?)

17
5 TYPES OF CHEM. RXNS.
  • 3. SINGLE REPLACEMENT
  • A BX --gtAX B
  • element compound --gt different compound
    different element

18
EXAMPLE
  • 1. iron copper II sulfate --gt iron II sulfate
    copper
  • 2. copper silver nitrate --gt copper II nitrate
    silver

19
5 TYPES OF CHEM. RXNS.
  • 4. DOUBLE REPLACEMENT ( ionic) (square dance)
  • AX BY --gt AY BX
  • compound compound --gt different compound
    different compound

20
EXAMPLE
  • 1. sodium chloride silver nitrate --gt sodium
    nitrate silver chloride

21
5 GENERAL TYPES OF CHEM. RXNS.
  • 5.
  • COMBUSTION
  • hydrocarbon oxygen --gt water carbon dioxide
  • Lets learn about hydrocarbons.
Write a Comment
User Comments (0)
About PowerShow.com