Transcript Trendy Periodic Table

Trendy Periodic Table
Period vs. Row

The periodic table is
labeled by its rows,
which are called
Periods.

The columns of the
Periodic Table are
called Groups or
Families.
Families
Metal, Metalloid, Nonmetal
Metals
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Become positive ions
(cations).
Conduct electricity.
Malleable.
Shine.
Usually a solid at room
temperature. High melting
points.
Nonmetals
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Become negative ions
(anions).
Do not conduct electricity or
heat.
Brittle.
Dull
Usually a gas at room
temperature. Low melting
points.
Metalloids:
Some properties of metals, some properties of nonmetals.
Atomic Radius
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Size increases down a group.
Size generally decreases across a period from left to right .
Ionization Energy
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The ionization energy of an atom is the amount of
energy required to remove an electron from the
gaseous form of that atom or ion.
1st ionization energy - The energy required to
remove the highest energy electron from a neutral
gaseous atom.
For Example:
Na(g) → Na+(g) + e-I1 = 496 kJ/mole
Notice that the ionization energy is positive. This is
because it requires energy to remove an electron.
Ionization Energy
Electron Affinity
Electron Affinity is the energy associated with the
addition of an electron to a gaseous atom.
 Example:
Cl(g) + e- → Cl-(g)E.A. = -349 kJ/mole
 Notice the sign on the energy is negative. This is
because energy is usually released in this process, as
apposed to ionization energy, which requires energy.
 A more negative electron affinity corresponds to a
greater attraction for an electron. (An unbound
electron has an energy of zero.)
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Electron Affinity
Electronegativity
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Electronegativity is an atom's 'desire' to grab
another atom's electrons. A high
electronegativity value implies that the valence
electrons are tightly held and require a large
amount of energy to remove.
Period - electronegativity increases as you go
from left to right across a period.
Group - electronegativity decreases as you go
down a group.
Electronegativity
Reactivity
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Reactivity refers to how likely or vigorously an atom is to
react with other substances. This is usually determined by how
easily electrons can be removed (ionization energy) and how
badly they want to take other atom's electrons
(electronegativity) because it is the transfer/interaction of
electrons that is the basis of chemical reactions.
Metals
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Period - reactivity decreases as you go from left to right across a
period.
Group - reactivity increases as you go down a group
Non-metals
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Period - reactivity increases as you go from the left to the right across a
period.
Group - reactivity decreases as you go down the group.
Ionic Radius
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Metals - the atomic radius of a metal is
generally larger than the ionic radius of the
same element.
Non-metals - the atomic radius of a non-metal
is generally smaller than the ionic radius of the
same element.
Melting Points

Metals - the melting point for metals generally
decreases as you go down a group.

Non-metals - the melting point for non-metals
generally increases as you go down a group.