REVIEW: Parts of the Atom

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REVIEW Parts of the Atom
Electron
Orbit
Neutron
Proton
Nucleus
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Element, Compound, or Mixture?
ELEMENT
COMPOUND
ELEMENT
MIXTURE
COMPOUND
MIXTURE
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Review of the Periodic Table
What is the symbol for Titanium? _________ What
is the atomic number of titanium? _________ How
many protons does titanium have? _________ How
many electrons does a neutral titanium atom
have? __________ What is the atomic weight for
titanium? _______________
Ti
titanium 22 47.867
22
Ti
22
22
47.867
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The Periodic Table

• The Periodic table as we know it today was
  arranged by a Russian Chemist named Mendeleev. He
  arranged it according to the physical and
  chemical properties of the elements

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WORKSHEET 1

• Complete the handout by writing the missing
  chemical symbols in each box.
• ON your periodic table (given last lesson) Label
  the following
• Alkali
• Alkaline Metals
• Transition Metals
• Poor metals
• Halogens
• Noble gases
• Non metals

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halogens
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Arranging Elements

• It is arranged in rows (across) called Periods
  and columns (down) called Groups
• Groups of elements show certain trends they
  have similar properties

Groups
Periods
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Trends On The Periodic Table
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Atomic Size

• Atoms have certain sizes depending on
• The amount of electrons (negatives)
• The pull from the nucleus (positive protons)
• For the third period (row) the atomic radius for
  each atom gets smaller across the table
• Even though the atoms have got more electrons
  their electronegativity (pull for electrons) is
  increasing because of increasing number of protons

Na Mg Al Si P S Cl Ar
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Electronegativity

• Electronegativity is the ability of a nucleus to
  attract its valence/bonding electrons. It follows
  certain trends on the table
• As you go across (left to right) it gets stronger
• As you go up it gets stronger

Na Mg Al Si P S Cl Ar
e-
e-
e-
e-
11
e-
e-
12
14
13
e-
e-
e-
16
15
e-
e-
17
e-
e-
e-
e-
e-
e-
What do you notice about the atomic number as you
go across the period?
e-
e-
What about the number of orbitals as you go
across the period?
19
e-
e-
What about the number of orbitals as you go down
a group?
e-
e-
K
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Size
Increasing size
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Trends From Left to Right

• Proton number and Atomic Mass increases
• Atomic size decreases (more protons pulling the
  electrons)
• Oxidising ability increases
• Form ionic compounds to forming covalent
  compounds
• Melting Points from relatively high to relatively
  low
• Form positive ions to form negative ions

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Trends down a group

• Proton number and Atomic Mass increases
• Atomic size increases (adding more orbitals)
• Metals become more reactive
• Non-metals become less reactive

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Valence Electrons

• Valence electrons (also known as valence) are the
  number of electrons present in the outer most
  orbital.

What is the valence of this sodium atom?
What is the valence of this chorine atom?
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Valence Electrons

• The number of valence electrons of an element is
  determined by its periodic table group in which
  the element is categorized.

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