Electron as Wave, Orbital Type and Electron Configuration for Students

8/6/2019 Electron as Wave, Orbital Type and Electron Configuration for Students

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Understand the concept of Bohr and electron

configuration

Describe quantum number and itsimportance

Identify and predict the atomic, period and

group number


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small bits of energy


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designated as by letter n and can have

positive integral values 1, 2,3,4.....


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Maximum number of electrons = 2n2


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What is the maximum number of electrons in

a given shell is given by 2n2. For the fifth

level, n=5, and so we have

2 x 52 = 2 x 25 = 50


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Hydrogen (Z=1) the single goes into the first

shell

Helium (Z=2) both goes to the first shell Lithium ( Z=3) two goes to the first and other

goes to the second shell


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Flourine and Aluminum

Flourine has a symbol F ( Z=9); two of theseelectron goes into the first shell and the

remaining seven go into the second levelF 2, 7


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Flourine and Aluminum

Aluminum ( Z=13) has 13 electronAl 2, 8, 3


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Where group does flourine belongs?What

about aluminum?

What have you observe with the groupings?


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What is the maximum number of electrons in

the fourth shell ( fourth energy level)?

32 electrons


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l = 0 designated by s and the shape of the

electron standing wave is spherical-like

l = 1 designated by p and the shape is dumbbell-like

l = 2 designated by d and the shape is four-lobedl = 3 designated by f and the shape is very

complicated


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Principal quantum number n corresponds to

the main energy level in which the electron

moves, that is 1,2,3 or K,L,M Azimuthal quantum number 1 gives and

measures the angular momentum of anelectron in its motion about the nucleus


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n l ml

Number of

orbitals

Orbital

Name

Number of

electrons

1 0 0 1 1s 22 0 0 1 2s 2

1 -1, 0, +1 3 2p 6

3 0 0 1 3s 2

1 -1, 0, +1 3 3p 6

2-2, -1, 0, +1,

+25 3d 10

4 0 0 1 4s 2

1 -1, 0, +1 3 4p 6

2-2, -1, 0, +1,

+25 4d 10

3-3, -2, -1, 0,+1, +2, +3

7 4f 14


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Magnetic quantum number m indicates the

behavior of the electrons in a magnetic field;

m may value from -1 to +1 including 0. Spin quantum number s indicates the spin of

an electron about its own axis in a clockwise(+) or counter clockwise (-) direction.


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The number of orbital types in a given shell is

equal to the shell number. Assume that n=

shell number or energy level, if n= 1, orbitaltype is 1.


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The different types of orbitals in order of

increasing complexity of shape as s,p,d,f.

The number of orbital s of a given typeincreases from type to type according to a

series of odd numbers beginning from 1

Paulis exclusion principles states that no less

than two electrons can occupy a given orbitaltype.


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The electron population of each shell or

energy level may be determined using the

formula 2n2 where n is equal to the numberof shell or energy level.


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ApartmentHouse Rules Electron Rules

From the Bottom Up:Rooms must be filled from

the ground floor up. Fill theone room on the first floorbefore starting to put new

tenants on the second floor.Then fill the s room before thep rooms. At higher floors theorder might change a bit.

Aufbau Principle:the electrons fill the available

orbitals from lowest energy tohighest energy. In the groundstate all the electrons are in

the lowest possible energylevel.


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Singles First:

the owner of the buildingwants to have the tenants

spread out as much aspossible. For that reasonsingles are placed in rooms

before couples. If couplesmust be placed into a roomthen all of the other rooms onthat floor must already have asingle in them.

Hunds Rule:

The electrons must be placedinto the orbitals in such a way

that no pairs are put togetherunless absolutely necessary.That is, single electrons must

be placed into boxes first andthen paired up if necessary.


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The first main energy level can have a

maximum number of two electrons.

The second main energy level can have amaximum number of thirty-two electrons (2s

orbitals, 6p, 10d, and 14 f orbitals)

An s-orbital can only have 2 electrons, a p-

orbital 6, and 1 d-orbital 10, and an f-orbital14


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The valence number is determined by

counting the number of electrons in the last

main energy level. A particular energy level may have orbitals

which may not be filled up due to highenergy.

Electron as Wave, Orbital Type and Electron Configuration for Students

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