Chemical Reactions - PowerPoint PPT Presentation

Loading...

PPT – Chemical Reactions PowerPoint presentation | free to download - id: 672a15-YTFmZ



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Chemical Reactions

Description:

Chemical Reactions Chemical and Physical Properties Chemical Changes rusting or oxidation chemical reactions Physical Changes changes of state density, color ... – PowerPoint PPT presentation

Number of Views:38
Avg rating:3.0/5.0
Slides: 42
Provided by: CharlesA163
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Chemical Reactions


1
Chapter 3
  • Chemical Reactions

2
Chemical and Physical Properties
  • Chemical Changes
  • rusting or oxidation
  • chemical reactions
  • Physical Changes
  • changes of state
  • density, color, solubility, melting, boiling
  • Extensive Properties depend on quantity
  • Intensive Properties do not depend on quantity

3
States of Matter
  • Changes from one state to another Physical
    Change
  • heating
  • cooling

4
Physical Change vs. Chemical Change
5
Physical Change vs. Chemical Change
6
Chemical Equations
for a reaction to occur molecules, atoms, ions
must interact with one another in the appropriate
orientation under the right conditions
H2 O2 H2O
  • Symbolic representation of a chemical reaction
    (chemical change) that shows
  • -reactants on left side of reaction
  • -products on right side of equation
  • -relative amounts of each using coefficients

7
Chemical Equations
  • Are an attempt to show on paper what is happening
    at the molecular level

8
Chemical Equations
  • Look at the information an equation provides
  • reactants products
  • 1 formula unit 3 molecules 2 atoms 3
    moles
  • (molecule/mole) (moles/f.u.)
    (moles/f.u.) (molecules.f.u.)
  • the states of matter also listed

9
Chemical Equations
10
Chemical Equations
  • Law of Conservation of Matter
  • Matter is neither created nor destroyed in a
    chemical reaction
  • -There is no detectable change in quantity of
    matter in an ordinary chemical reaction
  • -Balanced chemical equations must always include
    the same number of each kind of atom on both
    sides of the equation
  • Balancing equations is a skill acquired only with
    a lot of practice!!!
  • By working many problems

11
Balancing Composition Reactions
  • Na(s) Cl2(g) ? NaCl(s)
  • Mg(s) O2(g) ? MgO(s)
  • Al(s) Br2(l) ? AlBr3(s)

12
Balancing Reactions On Your Own
  • P4(s) O2(g) ? P4O10(s)
  • CO(g) O2(g) ? CO2(g)
  • P4(s) Cl2(g) ? PCl3(l)
  • SO2(g) O2(g) ? SO3(g)
  • P4O6(g) O2(g) ? P4O10(s)

13
Balancing Decomposition Reactions
  • N2O(g) ? N2(g) O2(g)
  • H2O2(aq) ? H2O(l) O2(g)
  • AgBr(s) ? Ag(s) Br2(l)
  • NH4HCO3(s) ? NH3(g) H2O(g) CO2(g)

14
Balancing Displacement Reactions on Your Own
  • AgNO3(aq) Cu(s) ? CuNO3(aq) Ag(s)
  • Al(s) H2SO4(aq) ? Al2(SO4)3(aq) H2(g)
  • Cl2(g) NaI(aq) ? I2(s) NaCl(aq)
  • CaCl2(aq) Na3PO4(aq) ? NaCl(aq)
    Ca3(PO4)2(s)
  • Ca(OH)2(aq) HNO3(aq) ? Ca(NO3)2(aq) H2O(l)
  • Ca(NO3)2(aq) K2CO3(aq) ? KNO3(aq) CaCO3(s)

15
Law of Conservation of Matter
  • Combustion reaction
  • the burning of a fuel in oxygen producing oxides
    or oxygen containing compounds
  • -NH3 burns in oxygen to form nitrogen monoxide
    and water

16
Law of Conservation of Matter
  • C7H16 burns in oxygen to form carbon dioxide and
    water.

17
Solutions
  • a mixture of two or more substances dissolved in
    another
  • Solute
  • substance present in the smaller amount that is
    dissolved by the solvent
  • Solvent
  • substance present in the larger amount that
    dissolves the solute

18
Properties of Aqueous Solutions
  • Electrolytes
  • produce ions in solution and conduct electricity
  • Strong electrolytes
  • ionize or dissociate 100 in water
  • NaCl(s)?Na(aq) Cl-(aq)
  • Weak electrolytes
  • ionize or dissociate much less than 100 in water
  • HF(l) H(aq) F-(aq)

19
Strong Electrolytes
  • conduct electricity extremely well in dilute
    aqueous solutions
  • -ionize in water 100
  • Examples
  • HCl, HNO3, etc
  • strong soluble acids
  • NaOH, KOH, etc
  • strong soluble bases
  • NaCl, KBr, etc
  • soluble ionic salts

20
Strong Ionic Salts
21
Weak Electrolytes
  • conduct electricity poorly in aqueous solutions
  • -ionize much less than 100 in water
  • Examples
  • CH3COOH, (COOH)2
  • weak acids
  • NH3, Fe(OH)3
  • weak bases

22
Properties of Aqueous Solutions
  • Nonelectrolytes
  • solutes that do not conduct electricity in water
  • do not ionize
  • Examples
  • C2H5OH ethanol
  • Sugars glucose, sucrose, etc.

23
Aqueous Solution Conductivity
24
Solubility
  • maximum amount of solute that can dissolve in a
    given amount of solvent
  • -defined as the amount of solute that dissolves
    in 100 g solvent
  • Unsaturated Solution
  • contains less than the maximum amount that
    dissolves
  • Saturated solution
  • contains the maximum amount that dissolves
  • Supersaturated solution
  • contains more than the maximum amount that
    normally dissolves

25
Solubility
  • Rules for determining solubility
  • soluble (dissolves) vs. insoluble (does not
    dissolve)

OH- and O2-, except Ba2
Figure 5.3 on page 179
26
Soluble Insoluble Exceptions
1. Group IA and ammonium salts (Li, Na, K, NH4) ___________
2. Acetates, nitrates, chlorates, perchlorates (CH3COO-, NO3-, ClO3-, ClO4-) ___________
3. most chlorides, bromides, and iodides (Cl-, Br -, I-) Salts formed with Ag, Hg2, Pb2
4. most fluorides (F-) Salts formed with Group IIA
5. most sulfates (SO42-) Salts formed with Group IIA (Ca2, Sr2, Ba2), Ag, Hg2, Pb2
6. most carbonates, phosphates, sulfides (CO32-, PO43-, S2-) Salts formed with Group IA and NH4 (rule 1)
7. most oxides (O2-) _______________________
8. most hydroxides (OH-) Salts formed with Group IA and Ca2, Sr2
27
Solubility
28
Metathesis Reactions
  • two ionic aqueous solutions are mixed and the
    ions switch partners
  • AX BY ? AY BX
  • Metathesis reactions remove ions from solution in
    3 ways
  • form H2O neutralization (acid-base reactions)
  • form an insoluble solid (precipitation reactions)
  • form a gas
  • -Ion removal is the driving force of metathesis
    reactions

29
Precipitation Reactions
  • Three representation
  • 1. Molecular equation
  1. 2. Total ionic equation

Ag(aq) NO3-(aq) Na (aq) Cl-(aq) ?
AgCl(s) Na (aq) NO3-(aq)
3. Net ionic equation
Ag(aq) Cl-(aq) ? AgCl(s)
30
Precipitation Reactions
  • 1. Molecular equation
  • 2.Total ionic reaction
  • 3. Net ionic reaction

31
Arrhenius Acids
  • substances that generate H3O (H) in aqueous
    solutions
  • -Strong acids ionize 100 in water

(l)
32
Bronsted-Lowry Acids
  • Substances that donate protons (H)
  • Strong Acids
  • Formula Name
  • HCl hydrochloric acid
  • HBr hydrobromic acid
  • HI hydroiodic acid
  • HNO3 nitric acid
  • H2SO4 sulfuric acid
  • HClO3 chloric acid
  • HClO4 perchloric acid

33
Acids
  • -Weak acids ionize lt100 in water

34
Acids
  • Common Weak Acids
  • Formula Name
  • HF hydrofluoric acid
  • CH3COOH acetic acid (vinegar)
  • HCN hydrocyanic acid
  • HNO2 nitrous acid
  • H2CO3 carbonic acid (soda water)
  • H3PO4 phosphoric acid

35
Arrhenius Bases
  • Substance that produce OH- ions in aqueous
    solution (water)
  • Strong bases ionize 100 in water

C
C
  • Weak bases are covalent compounds that ionize
    lt100 in water

(l)
36
Bronsted-Lowry Bases
  • Substances that accept protons (H)
  • Strong bases
  • LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2
  • Notice that they are all hydroxides of IA and IIA
    metals

37
Acid-Base (neutralization) Reactions
  • form water and salt (ionic compound)
  • acid base ? salt water
  • 1. Molecular equation

l
  • 2. Total ionic equation

(l)
  • 3. Net ionic equation

38
Acid-Base (neutralization) Reactions
  • 1. Molecular equation

(l)
  • 2. Total ionic equation

(l)
3. Net ionic equation
39
Acids and Bases
  • There are four acid-base reaction combinations
  • that are possible
  • strong acids strong bases
  • weak acids strong bases
  • strong acids weak bases
  • weak acids weak bases

40
Acids and Bases
  • Polyprotic acids
  • Have more than 1 hydrogen ion that it can donate
    to a base
  • 1 mol sulfuric acid reacts with 1 mol sodium
    hydroxide
  • H2SO4(aq) NaOH(aq) ? NaHSO4(aq) H2O(l)
  • 1 mol sulfuric acid reacts with 2 mols sodium
    hydroxide
  • H2SO4(aq) 2NaOH(aq) ? Na2SO4(aq) 2H2O(l)

41
Gas Forming Reactions
  • H2CO3 ? H2O(l) CO2 (g)
  • H2SO3 ? H2O(l) SO2 (g)
  • NH4OH ? NH3(g) H2O(l)
About PowerShow.com