Science, Matter

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Chapter 2

• Science, Matter Energy
• Janice Padula
• Clinton Community College

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Scientific Method

• EXPERIMENT - An observation of natural phenomena
  carried out in a controlled manner so that the
  results can be recorded, duplicated, and rational
  conclusions obtained.
• HYPOTHESIS - A tentative (unconfirmed)
  explanation of or prediction derived from
  experimental observations.
• MODEL An approximation or simulation of a
  hypothesis or system being studied.
• THEORY - A tested and widely accepted explanation
  of basic natural phenomena or scientific
  hypothesis.
• LAW - A concise verbal or mathematical statement
  that is always the same under the same natural or
  controlled conditions.

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Validity of Results

• Scientific Results (reputable scientific
  research)
• Can be disproved
• Can establish models theories and laws
• Can NOT prove absolute truth
• Frontier Science (like media reports)
• Controversial
• Not widely tested or accepted
• Consensus Science (open peer review)
• Widely accepted in the scientific community
• Junk Science (no peer review)
• False information presented in a scientific way
  that is meant to be misleading and is not
  accepted by the scientific community

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Types of Matter

• ATOM - The smallest particle of an element that
  retains the chemical properties of that element.
• ELEMENT - Matter that is composed of only one
  type of atom.
• MOLECULE - A definite group of atoms that are
  chemically bonded, i.e. tightly connected by
  attractive forces.
• COMPOUND - Matter that is composed of 2 or more
  elements combined in definite proportions.

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Law of Conservation of Mass

• Total mass remains constant throughout a chemical
  reaction
• ex. 2Hg O2 ---gt 2HgO, where the mass of the 2Hg
  2.53g and the mass of the 2HgO 2.73g, the
  mass of the O2 has to equal 0.20g.

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PROTONS

• PROTONS are defined as
• positively charged subatomic particles with a
  charge of 1.602x10-19 coulombs
• found inside the nucleus
• composed of 2 up quarks and 1down quark
• mass 1.672622x10-24 g or 1.007276 AMU
• The elements atomic number ( Z) protons

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NEUTRON

• NEUTRONS are defined as
• electrically neutral subatomic particle
• found inside the nucleus
• composed of 2 down quarks and 1 up quark
• mass 1.674927x10-24 g or 1.008665 AMU.

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NUCLEUS

• NUCLEUS is defined as
• core of the atom
• centrally located
• positively charged
• contains most of the atom's mass
• very dense
• small relative to the overall size of the atom

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ELECTRONS

• ELECTRONS are defined as
• negatively charged subatomic particle with a
  charge of -1.602x10-19 coulombs
• leptons
• found outside of the core of the atom
• mass 9.1x10-28 g or 0.00055 AMU
• travel in orbitals around the nucleus
• mostly empty space
• occupies most of the size of the atom

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ATOMS

• ATOMS are defined as
• smallest particle of an element that retains the
  chemical properties of that element
• composed of the nucleus (core) surrounded by
  electrons

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ISOTOPES

• ISOTOPES are defined as
• Atoms of the same atomic number but different
  mass
• B-10 Boron has 10 mass units, 5 protons 5
  neutrons
• B-11 Boron also can have 11 mass units, 5p 6n
• C-12 Carbon has 12 mass units, 6 protons 6
  neutrons
• C-14 Carbon has 14 mass units, 6 protons 8
  neutrons
• U-234 Uranium has 234 mass units, ?
• U-235 ?
• U-238 ?

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Periodic Table of Elements

• Periodic Table is a reference table of the 117
  elements that are currently identified, 92 are
  naturally occurring, which are displayed in
  periods (rows) and families (columns) so that
  similarities and differences can easily be
  recognized for use in the sciences
• See handout of Periodic Table
• Locate the interactive CD from my webpage and
  explore it

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Ions and Ionic Compounds

• Ions are atoms or groups of atoms that have lost
  or gained electrons resulting in an overall
  positive or negative charges.
• Ionic compounds are compounds formed by the
  combination of () and (-) ions. () ions
  are called cations
• (-) ions are called anions

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Common Polyatomic Ions

• carbonate ion CO3-2
• sulfate ion SO4-2
• sulfite ion SO3-2
• hydroxide OH-
• phosphate PO4-3
• permanganate MnO4-
• chromate CrO4-2
• dichromate Cr2O7-2

• ammonium NH4
• oxalate C2O4-2
• bicarbonate HCO3-2
• cyanide ion CN-
• acetate C2H3O2-
• peroxide O2-2
• thiosulfate S2O3-2
• bisulfite HSO3-

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Basic Chemicals in ENV 101

• H2O water CO2 carbon dioxide
• O2 oxygen NO2 nitrogen dioxide
• O3 ozone SO2 sulfur dioxide
• N2 nitrogen SO3 sulfur trioxide
• N2O nitrous oxide NH3 ammonia
• NO nitric oxide H2SO4 sulfuric acid
• H2S hydrogen sulfide HNO3 nitric acid
• C6H12O6 glucose CH4 methane
• CO carbon monoxide HCl hydrochloric acid

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Organic Compounds

• Hydrocarbons compounds composed of hydrogen and
  carbon ex. CH4, methane which is the major
  component in natural gas
• Chlorinated hydrocarbons hydrocarbons that have
  chlorines attached, ex. C14H9Cl5 , an insecticide
  which has been named DDT
• Simple carbohydrates simple sugars made up of
  carbon, hydrogen and oxygen, ex. C6H12O6, glucose
  which most plants and animals metabolize in their
  cells to produce energy

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Complex Organic Molecules

• Polymers consisting of a number of basic units
  (monomers) linked together
• Complex carbohydrates made up of monomers of
  simple sugars linked together
• Proteins formed by monomers of amino acids
  linked together
• Nucleic acids linked sequences of monomers
  called nucleotides
• Genes consist of nucleotides in DNA which carries
  code needed to make proteins
• Chromosomes are a combination of genes and
  proteins that make up DNA

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Physical States of Matter

• Solid - Relatively incompressible, has a fixed
  shape and fixed volume.
• Liquid - Has a fixed volume and takes the shape
  of its container, fluid, and incompressible.
• Gas (Vapor)- Takes the shape of its container,
  fluid, and is compressible.

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Physical vs. Chemical Change

• Physical Change Change that takes place in the
  form or phase of matter, but not in its chemical
  identity.
• Chemical Change Change that involves the
  combination, recombination, or separation of
  atoms with each other.

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The Balanced Equation

• 2Al(s) 3Br2(l) ? Al2Br6(s)
• The chemicals on the left are the reactants and
  the right are the products.
• The coefficient in front of the chemical denotes
  the stoichiometric relationship.

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Numerical Subscripts

• 2Al(s) 3Br2(l) ? Al2Br6(s)
• The numerical subscript represents the number of
  atoms present in the molecule
• ex. Br2 means that an atom of Br is bonded to
  another atom of Br
• Therefore Br-Br Br2

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Phases of Matter

• 2Al(s) 3Br2(l) ? Al2Br6(s)
• The subscript letters in parenthesis denote the
  phase of matter that the chemical is in.

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Energy

• Kinetic Energy energy of motion
• Potential energy energy at rest
• High-quality Energy high output and ability to
  do work
• Low-quality Energy low output

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Thermodynamics

• Thermodynamics is the study of heat energy
• Endothermic process is positive () and involves
  the absorption of heat
• Exothermic process is negative (-) and involves
  the release of heat
• Heat transfer
• Conduction
• Convection
• Radiant

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Nuclear Change

• Nuclear reactions case changes within the nucleus
  of an atom
• Natural Radioactive Decay occurs when an
  unstable isotope spontaneously releases particles
  from the atom Nuclear Fission occur when
  isotopes are split apart by bombardment with
  neutrons (see Figures 2-6 2-7 on pg 28)
• Nuclear Fusion occurs when 2 isotopes join
  together to form a heavier isotope

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What Is Light?

• Light is bundles of energy called PHOTONS that
  travel in waves through an electrical and
  magnetic field. (See Fig 2-8 on pg 29)
• Photons have no mass.
• Photons are released when electrons are
  de-excited from an excited state.

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What Are Waves?
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Whats a Wavelength?
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Systems

• def. System a set of components that function
  and interact together as a unit, which allows
  them to be studied
• Inputs gt Flows gt Outputs
• Feedback change in the same direction
• - Feedback change in the opposite direction

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Types of Pollutants

• Three factors are used to determine how
  severe a pollutant is
• Chemical nature the many chemical properties
  that a substance or compound has
• Concentration usually measured in ppm 1part
  pollutant/1 million parts matter or parts per
  billion (ppb)
• Persistence measure of how long a pollutant
  will remain in a system

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Types of Pollutants (cont.)

• Degradable or non-persistent easily broken down
  to safer non-toxic matter
• Biodegradable complex chemicals that are broken
  down through biological action (specific
  bacteria)
• Slowly degradable or persistent take decades or
  longer to degrade
• Non-degradable can not be broken down therefore
  they remain in the system and can contaminate a
  whole host of organisms

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Synergy

• Synergistic effect build up of effects that
  create a heightened or accelerated effect
• Ex. Exposure to a drug and drinking alcohol can
  create a heightened effect that may damage your
  liver, nervous system, heart etc. for more than
  the individual effects of each chemical.
• Ex. Different perfumes can combine and form
  noxious fumes in a closed room.

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Unsustainable High-Throughput vs.
Matter-Recycling Economy

• High-throughput economy economic growth by a
  one-way flow of matter and energy resources that
  produce large amounts of waste
• Matter-recycling economy economic growth
  slowing down depletion of matter resources in
  order to reduce excessive pollution

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Sustainable Low - Throughput

• Living more sustainably by reducing the
  throughput of matter and energy
• Not wasting matter energy
• Recycling reusing matter resources
• Stabilizing our population

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