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Matter and Energy

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II. Matter & Energy A. Principles of Chemistry B. Water C. Organic Compounds D. Energy Matter and Energy Principles of chemistry Water Organic compounds – PowerPoint PPT presentation

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Title: Matter and Energy


1
Matter and Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy
  • Principles of chemistry
  • Water
  • Organic compounds
  • Energy

2
Principles of Chemistry
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Atomic structure
  • The periodic table
  • Chemical bonding
  • Important elements in environmental processes

3
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Matter
  • Anything that takes up space and has mass
  • Atom
  • The smallest stable particle of matter
  • Composed of protons, neutrons, and electrons
  • Overall structure textbook figure 2.3

4
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Protons
  • Positively charged
  • Atomic mass ? 1 atomic mass unit
  • Located in the nucleus of an atom
  • Neutrons
  • Electrically neutral
  • Atomic mass ? 1 atomic mass unit
  • Located in the nucleus of an atom

5
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Electrons
  • Negatively charged
  • Atomic mass very small, almost negligible
  • Located in electron shells (orbitals) around the
    nucleus
  • In a neutral atom, the number of electrons and
    protons is the same
  • Atoms can lose or gain electrons during chemical
    bonding

6
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Element
  • A substance composed of only a single type of
    atom
  • Atomic number of an element
  • The number of protons in its atoms
  • The atomic number is the same for all atoms of an
    element
  • Mass number of an element
  • The number of protons plus the number of neutrons
    in its atoms
  • The atoms of an element may have a variable
    number of neutrons

7
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Isotopes of an element
  • Different forms of an element with the same
    atomic number but with different mass numbers
  • The atoms of some isotopes are stable
  • Other isotopes are radioactive, having unstable
    atoms that spontaneously break apart (decay) to
    form other atoms
  • When radioactive atoms decay, energy is released

8
A.1. Atomic Structure
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • For example, carbon has three isotopes
  • Carbon-12, with 6 protons and 6 neutrons, is the
    most common form of carbon
  • Carbon-13, with 6 protons and 7 neutrons, is
    stable (non-radioactive) and rare
  • Carbon-14, with 6 protons and 8 neutrons, is
    unstable (radioactive) and rare

9
A.2. The Periodic Table
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Textbook figure 2.2
  • In the periodic table
  • Elements are listed in order of their atomic
    numbers
  • Elements are designated by standard one or
    two-letter abbreviations
  • Elements in the same vertical column often have
    very similar chemical bonding properties

10
A.2. The Periodic Table
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Notable groups in the periodic table
  • Metals, nonmetals, and metalloids
  • Halogens
  • Nobel gases
  • Heavy metals
  • Synthetic elements (larger than uranium)

11
A.3. Chemical Bonding
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Chemical bonding occurs when two or more atoms
    combine
  • Atoms combine by exchanging or sharing electrons
    in their outermost electron shell
  • Chemical compound
  • Formed when the atoms of two or more different
    elements combine by chemical bonding
  • Properties of a compound are usually very
    different than those of its elements

12
A.3. Chemical Bonding
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Ionic bonds
  • Formed when electrons are completely transferred
    from one atom to another
  • The atom that gains electrons becomes a negative
    ion (anion)
  • The atom that loses electrons becomes a positive
    ion (cation)
  • Example Sodium chloride Na Cl ? Na Cl

13
A.3. Chemical Bonding
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Covalent bonds
  • Form when two atoms share one or more pairs of
    electrons
  • Molecule consists of two or more atoms that are
    joined by covalent bonding
  • Covalent bonds are generally more stable than
    ionic bonds in aqueous (water) solution
  • Examples textbook, figures 2.4 2.6

14
A.4. Important Elements
II. Matter Energy A. Principles of
Chemistry 1. Atomic structure
2. The periodic table 3. Chemical
bonding 4. Important elements B.
Water C. Organic Compounds D. Energy
  • Textbook, table 2.1

15
Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Structure of water
  • Ionization of water
  • Solvent properties of water
  • Thermal properties of water

16
B.1. Structure of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • A water molecule is composed of two hydrogen
    atoms covalently bonded to an oxygen atom
  • The hydrogen atoms form an angle of about 110,
    so the molecule is bent

17
B.1. Structure of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • The oxygen nucleus exerts a greater pull on the
    electrons in the covalent bonds
  • Therefore, the oxygen atom has a partial negative
    charge
  • And the hydrogen atoms have partial positive
    charges

18
B.1. Structure of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Because opposite charges attract each other,
    water molecules are attracted to each other and
    to other charged molecules or ions

19
B.1. Structure of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • The bent geometry of water and the attraction
    between water molecules gives rise to unique
    properties that are essential for its role in
    living organisms and the environment

20
B.2. Ionization of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Consider a glass of pure water
  • In a tiny fraction of the water molecules (1 out
    of 10 million), one of the hydrogen nuclei is
    completely pulled off the molecule
  • This forms two ions
  • A hydrogen ion (H)
  • And a hydroxyl ion (OH)
  • This is caused by the attraction of the water
    molecules for each other

21
B.2. Ionization of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Water molecules are continuously splitting into
    ions and rejoining to form water molecules

22
B.2. Ionization of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • In chemically pure water, the number of H and
    OH ions are the same
  • Certain chemical substances, when dissolved in
    water, can change the amounts of H or OH

23
B.2. Ionization of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Acid
  • A substance that increases the amount of H (and
    decreases the amount of OH)
  • Base (Alkaline)
  • A substance that increases the amount of OH
    (and decreases the amount of H)
  • Neutral substance
  • A substance that does not change the amounts of
    H and OH (so H remains equal to OH)

24
B.2. Ionization of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Acidity and alkalinity are represented by a value
    called pH
  • Acids pH value is less than 7
  • Bases pH value is greater than 7
  • Neutral substances pH value is equal to 7
  • Each pH value represents a 10-fold change in the
    amount of H in the solution
  • So a substance with pH 5 has a 10 times greater
    amount of H than a substance with pH 6
  • Textbook, figure 2.5

25
B.3. Solvent Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Solution
  • A mixture of two (or more) different substances
    in which the particles of one substance are
    completely interspersed with the particles of the
    other substance(s)
  • Solvent The substance that is present in the
    largest amount
  • Solute The substance(s) that are present in
    smaller amounts

26
B.3. Solvent Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Hydrophilic substances
  • Substances that can be dissolved in water
  • Water molecules are attracted to ions or to other
    molecules that have partial positive and negative
    charges
  • Examples of hydrophilic substances
  • Sodium chloride (table salt) This substance
    consists of sodium ions and chloride ions
  • Sucrose (table sugar) This substance is a
    compound with many -OH groups in its structure,
    with many partial positive and negative charges

27
B.3. Solvent Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Hydrophobic substances
  • Substances that cannot be dissolved in water
  • Water molecules have difficulty interacting with
    uncharged molecules. These substances tend to
    separate from water.
  • Example of a hydrophobic substance
  • Cooking oil The molecules of cooking oil have
    long chains of carbon atoms bonded to hydrogen.
    The atoms do not have the bent geometry of
    water, so there are no partial charges to attract
    the water.Therefore, oil and water dont mix!

28
B.3. Solvent Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Amphipathic substances
  • Substances in which part of the molecule is
    hydrophobic, and part of the molecule is
    hydrophilic
  • When amphipathic substances are mixed in water,
    its molecules form into clusters called
    micelles
  • with the hydrophilic part on the outside of the
    micelle in contact with water
  • and the hydrophobic part on the inside of the
    micelle, away from the water .

29
B.3. Solvent Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Amphipathic substances (cont.)
  • Example of an amphipathic substance
  • Soap Soap molecules have an ionic group attached
    to one end, and an oily hydrocarbon chain
    attached to the other end. When soap is mixed
    with water, it forms micelles that trap oily dirt
    molecules.

30
B.4. Thermal Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Molecules are in constant motion due to the heat
    energy (kinetic energy) they contain
  • Phases of matter
  • Solid
  • Limited movement of molecules non-fluid
  • Liquid
  • Molecules can move freely around each other
    fluid
  • Gas
  • Molecules have greatest freedom of movement
    substance can expand to fill the available space

31
B.4. Thermal Properties of Water
II. Matter Energy A. Principles of
Chemistry B. Water 1. Structure of
Water 2. Ionization of Water
3. Solvent Properties 4. Thermal
Properties C. Organic Compounds D.
Energy
  • Water has unusual thermal properties because of
    the attraction of water molecules for each other
  • Water has relatively high melting and boiling
    points
  • Water remains in a liquid state over a wide
    temperature range
  • Water has a high heat capacity it can absorb a
    large amount of heat with a small change in
    temperature
  • The solid form of water (ice) is less dense than
    the liquid, so ice floats on water

32
Organic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Bonding of carbon
  • Monomers and polymers
  • Bioorganic compounds

33
C. 1. Bonding of Carbon
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Carbon can form four covalent bonds with other
    atoms, such as nitrogen, oxygen, phosphorus,
    sulfur, halogens, and other carbons
  • Compounds formed from the covalent bonding of
    carbon are called organic compounds
  • Carbon-carbon bonds are very stable, allowing the
    formation of very large organic molecules

34
C. 1. Bonding of Carbon
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Hydrocarbons
  • Consist of carbon and hydrogen
  • Usually hydrophobic
  • Aromatic hydrocarbons contain one or more benzene
    rings (phenyl groups)

35
C. 2. Monomers and Polymers
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Monomer
  • An organic molecule that serves as a building
    block to build larger organic molecules
  • Polymer
  • An organic molecule composed of two or more
    monomer units linked together by covalent bonds

36
C. 2. Monomers and Polymers
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Condensation reaction
  • Polymers are often formed by the process of
    condensation
  • In this process, two hydrogen atoms and an oxygen
    atom are removed from two monomer units
  • And a covalent bond forms between the monomers

37
C. 2. Monomers and Polymers
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
38
C. 2. Monomers and Polymers
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Hydrolysis reaction
  • Polymers are often broken down by the process of
    hydrolysis
  • In this process, a water molecule is inserted
    between the monomer units of a polymer
  • To split the polymer into its monomer units

39
C. 2. Monomers and Polymers
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
40
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Textbook, figure 2.6 table 2.2
  • Carbohydrates
  • Composed mostly of carbon, hydrogen, and oxygen
  • Large number of OH groups attached to the
    carbons
  • Functions
  • Energy source for living cells
  • Certain structural components of cells

41
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Carbohydrates (cont.)
  • Monosaccharides
  • Simple sugars
  • Monomer unit of carbohydrate group
  • Examples Glucose, fructose
  • Disaccharides
  • Composed of two monosaccharide units joined
    together
  • Examples Sucrose, lactose
  • Polysaccharides
  • Composed of multiple monosaccharide units (100s
    1000s)
  • Examples Starch, glycogen, cellulose

42
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Lipids
  • Biological compounds with hydrophobic components
    in their molecular structures
  • Functions
  • Energy storage
  • Structural components
  • Glycerides
  • A major class of lipid
  • Composed of a glycerol molecule attached to one,
    two, or three fatty acid molecules

43
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Lipids (cont.)
  • Generalized structure of a triglyceride

44
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Proteins
  • Composed of chains of amino acids
  • There are 20 different amino acids, each with
    distinctive chemical properties
  • A protein molecule may contain several hundred
    amino acids
  • Each different protein has its own order, or
    sequence, of amino acids
  • The correct sequence of amino acids is essential
    for the proteins function

45
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Proteins (cont.)
  • Functions
  • Enzymes Enzymes are biological catalysts that
    control almost every reaction in living systems
  • Cellular recognition and communication
  • Structural components of living cells

46
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Nucleic acids
  • Composed of chains of nucleotides
  • There are 4 different nucleotides
  • A nucleic acid molecule may contain several
    thousands or millions of nucleotides
  • Each nucleic acid molecule has its own order, or
    sequence, of nucleotides
  • The correct sequence of nucleotides is essential
    for the nucleic acids function

47
C. 3. Bioorganic Compounds
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds 1. Bonding of Carbon
2. Monomers Polymers 3. Bioorganic
compounds D. Energy
  • Nucleic acids (cont.)
  • Overall function
  • The sequence of nucleotides in a nucleic acid
    molecule serves as a blueprint to encode the
    correct sequence of amino acids for a protein.
    The code for a specific protein is called a
    gene.
  • Deoxyribonucleic acid (DNA) DNA molecules
    (chromosomes) serve as the master blueprint for
    all of the cells proteins. The DNA molecules are
    transmitted to offspring during reproduction.
  • Ribonucleic acid (RNA) RNA molecules serve as
    working copies of the genes for the proteins
    that the cell is making at any given time.

48
Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Types of energy
  • Oxidation and reduction
  • Electrical generation

49
D. 1. Types of Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Energy
  • The ability to do work
  • The capacity to change matter
  • Kinetic energy and potential energy
  • Kinetic energy
  • Energy associated with movement
  • Energy released as a process occurs
  • Potential energy
  • Stored energy that is contained in matter
  • The potential of matter for undergoing change

50
D. 1. Types of Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Heat
  • Energy associated with the movement of molecules
  • Electromagnetism
  • Energy associated with electrical charges and
    magnetic fields
  • Electric current is produced by electrons flowing
    through a conductor (such as a copper wire)

51
D. 1. Types of Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Electromagnetic radiation
  • Energy that travels through space in the form of
    packets of energy waves called photons
  • The amount of energy in a photon is related to
    its wavelength the shorter the wavelength, the
    more energy the photon has
  • Photons can interact with matter to cause
    different affects, depending on the energy of the
    photons
  • Textbook, figure 2.9

52
D. 1. Types of Energy
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Chemical energy
  • Energy associated with the making or breaking of
    chemical bonds
  • Exothermic reaction
  • A chemical reaction in which energy is released
  • Endothermic reaction
  • A chemical reaction in which energy is absorbed
  • Atomic energy
  • Energy released when radioactive isotopes split
    apart (atomic fission) or fuse together (atomic
    fusion)
  • Textbook, figure 12.9

53
D. 2. Oxidation and Reduction
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Energy is associated with the gain or loss of
    electrons by atoms in chemical reactions
  • Reduction reaction
  • A reaction in which an atom gains electrons
  • By becoming bonded to a less electronegative atom
    (such as hydrogen)
  • Compounds with more reduced atoms often have a
    larger amount of potential chemical energy (in an
    oxygen atmosphere)

54
D. 2. Oxidation and Reduction
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Oxidation reaction
  • A reaction in which an atom loses electrons
  • By becoming bonded to a more electronegative atom
    (such as oxygen)
  • Compounds with more oxidized atoms often have a
    smaller amount of potential chemical energy (in
    an oxygen atmosphere)
  • Oxidation and reduction reactions always occur
    together one substance is oxidized, and another
    substance is reduced.

55
D. 2. Oxidation and Reduction
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Examples
  • Oxidation of methane (natural gas)
  • 2 CH4 4 O2 2 CO2 4 H2O Energy (Heat
    Light)
  • Reduction of CO2 to form glucose in
    photosynthesis
  • 6 CO2 6 H2O Energy (Light) C6H12O6 6 O2

56
D. 3. Electrical Generation
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Electric current
  • The movement of electrons through a conductor
    (such as a copper wire)
  • Electrical generator
  • When a conductor (such as a copper wire) is moved
    in a magnetic field, a current is generated in
    the wire
  • By moving a coil of wire within a strong magnetic
    field, large electrical currents can be generated

57
D. 3. Electrical Generation
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
58
D. 3. Electrical Generation
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Types of generators
  • Coal, oil, and natural gas generators
  • Pressurized steam is generated by boiling water,
    using fossil fuels as an energy source
  • The steam pressure is used to run turbines that
    are attached to the generator coils
  • Hydroelectric generators
  • The energy from falling water (from waterfalls or
    dams) is used to run turbines that are attached
    to generator coils

59
D. 3. Electrical Generation
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Types of generators (cont.)
  • Nuclear generators
  • The tremendous heat from a nuclear chain reaction
    is used to generate pressurized steam
  • The steam pressure is used to run a turbine that
    is attached to the generator coils
  • Textbook, figures 12.9 12.11
  • Other methods
  • Windmill generators
  • Tidal power generators (Figure 12.30)

60
D. 3. Electrical Generation
II. Matter Energy A. Principles of
Chemistry B. Water C. Organic
Compounds D. Energy 1. Types of
energy 2. Oxidation and reduction
3. Electrical generation
  • Other methods of generating electricity
  • Chemical cells (batteries)
  • Uses chemical oxidation and reduction
  • Often, the cells contain substance (such as heavy
    metals) that are difficult to dispose
  • Figure 12.23
  • Photovoltaic cells
  • Crystals of certain substances produce an
    electrical current when exposed to light
  • Figure 12.20
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