106139428 trends in the periodic table

8/10/2019 106139428 Trends in the Periodic Table

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Trends in the

Periodic Table


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Trends in the Periodic Table

Properties of elements change in

a predictable way as you move

through the periodic table. These

systematic variations are called

periodic trends.


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Summary


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Trends in the Periodic Table

Properties of elements change in

a predictable way as you move

through the periodic table. These

systematic variations are called

periodic trends.


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Atomic Radius

Atomic size increases as

you move from top to bottom

in a family. This is because theenergy level increases when

you go down the periodic

table.


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Atomic Radius

Atomic size decreases as you

move from left to right. This is

because the number of electronsand protons increases but there

are no changes in the energy

level, thus increasing theattracting forces making the

radius smaller.


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Atomic Radius


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Ionic Radii

When an atom loses an

electron or becomes a

positive ion, it becomessmaller. The repulsive force

of electrons decreases

drawing the electrons closer

to the nucleus. The result is a

smaller radius.


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Ionic Radii

When an atom gains an

electron or becomes a

negative ion, it becomeslarger. This is due to the

increase of the repulsive

force of electrons increasing

the radius of the ion.


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Ionic Radii


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Atomic and Ionic Radii


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Ionization Energy

The energy required to remove anelectron from an atom to form an

ion.

The ionization increases when anelectron is removed, because once

this happens, the protons will have

higher energy drawing them closer to

the nucleus. The attracting force

increases thus requiring more energy

to release the second electron.


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Ionization Energy

The ionization energy

decreases from top to

bottom because when theenergy level increases, the

electrons moves farther away

from the nucleus decreasing

the attracting force from the

nucleus.


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Ionization Energy

Another is that the

electron is shielded by the

inner sub-shell, thus lesserenergy reaches the last

electron.


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Ionization Energy

The ionization energy

increases from left to right

because there are moreelectrons in the outer most

energy level, this increases the

attraction of the electrons andprotons thus pulling them closer

to the nucleus.


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Ionization Energy

The closer they are to

the nucleus, the harder

for them to be removed.

Thus, requires more

ionization energy.


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Ionization Energy


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Ionization Energy


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Electron Affinity

The amount of energy

released or absorbed when an

atom accepts an electron givingit a negative charge. For most

elements, energy is released

when an atom adds an electron.This is also the measure of an

element to attract an electron to

form a negative ion.


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Electron Affinity

Electron affinity

increasesfrom left to right

and decreases from top tobottom in a group or

family.


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Electron Affinity


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Electronegativity

The ability of an element

to attract an electron.

The scale of relativeelectronegativities, which F is

the most electronegative, the

value was developed by Linus

Pauling.


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Electronegativity

Electronegativity increases

from left to right and

decreases from top tobottom. This would tell that

metalshave the tendencies to

lose electrons and the non-

metals to gain electrons.


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Electronegativity

106139428 trends in the periodic table

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