Chapter 2 Atoms, Molecules and Ions

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Chapter 2Atoms, Molecules and Ions
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What is in an atom?

• Name the three subparticles that make up an atom
• 1.
• 2.
• 3.

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Who Discovered Them?

• http//www.physlink.com/Education/AskExperts/ae46.
  cfm

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Label the following
http//www.chemcool.com/referencetables/periodicta
ble.htm
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PRACTICE PROBLEMSCalculate the of protons,
electrons, or neutrons for the following elements
http//www.dayah.com/periodic/
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Critical Thinking

• Of the three subabomic particles, which one gives
  the identity to the element? WHY? Explain
• 2. List at least three facts about the Nucleus.

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WEBQUEST!!

• Today we are going to use the Internet to
  research the timeline of the discovery of the
  atom!

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Nuclear Stability Radioactivity

• Radioactivity
• Nuclear reactions Reactions that change in the
  _______________ _____________ and produce
  ____________________.
• Three kinds of radiation occur
• 1.
• 2.
• 3.

http//library.thinkquest.org/17940/texts/radioact
ivity/radioactivity.html
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Nuclear Stability

• Almost all the atoms you encounter have a
  ______________ nuclei ? not ________________.
• Radiation in __________________.
• What makes a nucleus unstable? Lets see (and
  think)..
• Review Nucleus is made up of ____________ and
  _______________.
• Review Positive charges _________________ each
  other.

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So why dont the protons fly apart from the
nucleus?

• There is a strong force that overcomes the
  electrical repulsion known as the Strong
  ________________ force.
• The neutron does _______________ experience and
  electrical repulsion because it has
  ______________ charge. It does however help in
  lessening the repulsion of the protons. The
  neutron is the glue that holds the nucleus
  together.

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• Elements between ______________ and ___________(
  ______________ to ____________) stable nuclei
  have ________________ number of protons and
  neutrons.
• After _____________ protons the nucleus needs
  more ________________ to be stable.
• After _____________ protons (_________________)
  no number of neutrons is sufficient to
  _________________ the nucleus together
  indefinitely. After 83 ? ________________.

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Types of Decay

• Radioactive elements emit different kinds of
  radiation
• They are distinguished by their charge mass and
  _______________ power.

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Charge and penetration powerAlpha (a)

• A stream of high alpha particles which is made of
  2 _____________ and 2 __________ (identical to
  the He2 nucleus) ? __________________.
• Does not have much _____________ power.
• Travel only a few _____________ and may be
  stopped by paper or clothing

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Charge and penetration power Beta (ß)

• A stream of high speed ___________ . NOT the
  electrons that come from the orbital of the atom,
  the electron must come from the NUCLEUS.
• A NEUTRON CHANGES INTO A ________________ (which
  remains in the nucleus) AND AN ___________.
• The beta particle (or electron) is
  propelled out of the nucleus at _____________
  speed.
• Beta radiation is about 100 times more
  penetrating than alpha radiation. It can
  penetrate 1-2 millimeters into solid material.
• MAY pass through ___________ and damage skin.

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Charge and penetration power Gamma (?)

• A very energetic form of light that our eyes
  ____________ see.
• Does not consist of particles.
• Sybolized
• It is able to penetrate deeply into a solid
  material, including body tissue. VERY DANGEROUS.

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Nuclear reactions

• Nuclear reactions A reaction that keeps track of
  reactants components.
• Alpha
• Beta

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The Molecule

• Different Formulas
• Molecular
• Empirical
• Structural

http//dbhs.wvusd.k12.ca.us/webdocs/Mole/Empirical
Formula.html
http//dl.clackamas.edu/ch106-01/strform.htm
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The ION
http//www.launc.tased.edu.au/online/sciences/Phys
Sci/pschem/ion/Ions.htm

• Cation
• Anion

http//www.launc.tased.edu.au/online/sciences/Phys
Sci/pschem/ion/Cations.htm
http//www.launc.tased.edu.au/online/sciences/Phys
Sci/pschem/ion/Anions.htm
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Examples

• Indicate the number of protons, neutrons and
  electrons for the following
• 1. Sodium atom ? Sodium ion

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Example 2

• 2. Chlorine atom ? Chlorine ion

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Try These!
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Isotopes

• H1 (hydrogen) ________p, ________e, ________n
  (99.9844)
• H2 (deutrerium)________p, ________e, ________n
  ( .0156)
• H3 (tritium) _________p, ________e,
  ________n (0.0004)

http//www.colorado.edu/physics/2000/isotopes/
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http//www.dayah.com/periodic/
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About The Periodic TableDefine These

• Family/Group
• Period
• Main group elements
• Characteristics of the periodic table

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Characteristics
http//chemistry.about.com/od/elementgroups/a/nonm
etals.htm
http//chemistry.about.com/od/elementgroups/a/meta
ls.htm
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Characteristics

• Semi-Metals

http//chemistry.about.com/od/elementgroups/a/meta
lloids.htm
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Writing Compounds

• First What are the charges of each family on the
  periodic table?

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Criss-Cross Method

• For Ionic Compounds ONLY!!

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Names of compounds

• . Monatomic cations Take the name of the
  ______________ from which they are derived,
• Na __________________ K
  ____________________
• EXCEPT Many _____________________ metals can
  form more than one type of cation. A
  ___________________________ is added to tell the
  difference.
• a. Fe 2 _________________ Fe 3
  __________________

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Monatomic anions

• Add the suffix _________ to the end of the stem
  from which they are derived.
• N 3- _______________________
• O 2- ____________________
• S 2-___________________ (pg.43)

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Polyatomic IonsMEMORIZE THESE!
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REVIEW

• Ionic Compounds (REVIEW Ions are made up of a
  ______________ and a __________________.) First
  name the _____________________ then the
  ____________________.
• Binary Molecular Coupounds (REVIEW Molecules
  are made up of a ______________ and a
  __________________.)

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Diatomic molecules

• Diatomic molecules
• What are the diatomic molecules?

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Rules for Naming molecules

• Rules are the same as ionic compounds however,
  now include prefixes Mono is only for second
  element!!!
• 2. Prefixes
• 1 6
• 2 7
• 3 8
• 4 9
• 5 10

Mono is only for second element!!!
http//www.chemistry.ohio-state.edu/woodward/ch12
1/ch2_naming.htm
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Examples

• N2O3
• NF3
• PCl5
• P2O5
• O2
• CO2

http//www.chem4kids.com/files/atom_naming.html
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Flow Chart

• If you are a visual person, this might make
  naming compounds easier
• http//dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/H
  O6-Flowchart-Naming.pdf

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Common names of molecules Memorize these!
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Naming Acids

• Certain binary molecular compounds that start
  with ________ form acids when combined with
  ____________.

http//antoine.frostburg.edu/chem/senese/101/compo
unds/slides/sld009.htm
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Review With These

• http//www.cottonchemistry.bizland.com/chapter9/Ch
  apter20920Chemical20Names20and20Formulas.ppt