Matter and Energy

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Transcript Matter and Energy

II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
D. Energy
A.
B.
C.
D.
II.
Matter and Energy
Principles of chemistry
Water
Organic compounds
Energy
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
1.
2.
3.
4.
A. Principles of Chemistry
Atomic structure
The periodic table
Chemical bonding
Important elements in environmental
processes
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
A.1. Atomic Structure
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
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
A.1. Atomic Structure
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
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
A.1. Atomic Structure
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
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
A.1. Atomic Structure
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
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
A.1. Atomic Structure
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
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
A.1. Atomic Structure
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
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
A.2. The Periodic Table
Textbook: figure 2.2
In the periodic table
– Elements are listed in order of their atomic numbers
– Elements are designated by standard one or twoletter abbreviations
– Elements in the same vertical column often have
very similar chemical bonding properties
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
A.2. The Periodic Table
Notable groups in the periodic table
–
–
–
–
–
Metals, nonmetals, and “metalloids”
Halogens
Nobel gases
Heavy metals
Synthetic elements (larger than uranium)
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
A.3. Chemical Bonding
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
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
A.3. Chemical Bonding
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–
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
A.3. Chemical Bonding
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
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
A.4. Important Elements
Textbook, table 2.1
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
1.
2.
3.
4.
B. Water
Structure of water
Ionization of water
Solvent properties of water
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
B.1.
Structure of Water
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”
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
B.1.
Structure of Water
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
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
B.1.
Structure of Water
Because opposite charges attract each other,
water molecules are attracted to each other and
to other charged molecules or ions
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
B.1.
Structure of Water
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
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
B.2.
Ionization of Water
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
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
B.2.
Ionization of Water
Water molecules are continuously splitting into
ions and rejoining to form water molecules
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
B.2.
Ionization of Water
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–
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
B.2.
Ionization of Water
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–)
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
B.2.
Ionization of Water
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
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
B.3.
Solvent Properties of Water
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
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
B.3.
Solvent Properties of Water
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
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
B.3.
Solvent Properties of Water
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 don’t mix!
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
B.3.
Solvent Properties of Water
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 .
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
B.3.
Solvent Properties of Water
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.
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
B.4. Thermal Properties of Water
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
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
B.4. Thermal Properties of Water
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. Organic Compounds
1. Bonding of carbon
2. Monomers and polymers
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
C. 1.
Bonding of Carbon
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 1.
Bonding of Carbon
Hydrocarbons
– Consist of carbon and hydrogen
– Usually hydrophobic
– Aromatic hydrocarbons contain one or more
benzene rings (phenyl groups)
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 2.
Monomers and Polymers
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 2.
Monomers and Polymers
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
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
C. 2.
Monomers and Polymers
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
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
C. 3.
Bioorganic Compounds
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
Lipids (cont.)
– Generalized structure of a triglyceride:
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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 protein’s function
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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 acid’s function
II. Matter & Energy
A. Principles of Chemistry
B. Water
C. Organic Compounds
1. Bonding of Carbon
2. Monomers & Polymers
3. Bioorganic compounds
D. Energy
C. 3.
Bioorganic Compounds
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 cell’s 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.
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
D. Energy
1. Types of energy
2. Oxidation and reduction
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
D. 1.
Types of Energy
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
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
D. 1.
Types of Energy
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)
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
D. 1.
Types of Energy
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
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
D. 1.
Types of Energy
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
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
D. 2.
Oxidation and Reduction
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)
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
D. 2.
Oxidation and Reduction
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.
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
D. 2.
Oxidation and Reduction
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
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
D. 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
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
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
D. 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
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
D. 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)
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
D. 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