Gen Chem - ELECTRON STRUCTURE

Atomic Orbitals

Region of space in which there is a high probability of finding an electron

Louis de Broglie

“Electrons behave with wave and particle properties at the same time”

-Founder of the wave-particle theory

Werner Heisenberg

“It is impossible to know both the position and velocity of an electron simultaneously”

Erwin Schrodinger

Refined the wave-particle theory proposed by de Broglie. Developed an equation that treated an electron like a wave and predicted the probable location of an electron around the nucleus called the atomic orbital

The Quantum Mechanical Model

Determines the allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus

Fuzzy Cloud

The probability of finding an electron within a certain volume of space surrounding the nucleus can be represented as a ____

Orbital (Electric Cloud)

Region in space where there is a 90% chance of finding an electron

s-orbitals

Spherical shaped orbitals; One shape

p-orbitals

Dumbell shaped orbitals; Three different shapes

d-orbital

5 different shape orbitals

f-orbital

7 different type of shape orbitals

Principal Quantum Number (n)

Represents the “shell number” in which an electron “resides”

n=1, 2, 3, 4

Magnetic Quantum Number (ml)

Distinguishes orbitals within a given sub-shell that have different shapes and orientations in space.

Spin Quantum Number (ms)

Refers to the two possible spin orientation of the electrons residing within a given orbital.

The possible values are +1/2 and -1/2

Pauli Exclusion Principle

Defined as a fundamental principle stating that two atomic constituents, such as electrons, can occupy the same quantum state simultaneously, preventing them from occupying the same space at the same time.

Aufbau Principle

States that, in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy level before occupying higher-energy levels

Hund’s Rule

-Used to predict the ground state of an atom or molecule with one or more open atomic shells

-The lowest energy arrangement is the one with the greatest number of unpaired electrons. This implies that if two or more orbitals of equal energy are available, electrons will occupy them singly before filling them in pairs.

Periodic Table

is an arrangement of elements according to increasing atomic number so that elements of the same valence electrons fall in the same column.

Dmitry Mendeleev

Russian chemist publish the first version of a systematically organized periodic table of elements.

Vertical Columns

Called groups or families in the periodic table

Horizontal Rows

Called periods or series in the periodic table

Periodic Law

“When elements are arranged in order of increasing atomic number, there is a periodic pattern in their physical and chemical properties.”

“When arranged by increasing atomic number, the chemical elements display a regular and repeating pattern of chemical and physical properties.”

Group A Elements

These are the longer columns and are classified as Representative elements or main group elements

Group B Elements

These are the shorter columns that are called Transition Metals

Alkali Metals

Group IA

Alkaline Earth Metals

Group IIA

Boron Group

Group IIIA

Carbon Group

Group IVA

Oxygen Group

Group VIA

Nitrogen Group

Group VA

Halogens

Group VIIA

Noble Gases

Group VIIIA

Transition Metals

Group IIIB

Periodicity

Is a regular periodic variation of properties of elements with atomic number and positions in the periodic table.

Atomic Radius

Refers to the distance from the center of the nucleus to the surface of the neighboring atom.

Effective Nuclear Charge

the attractive positive charge of nuclear protons acting on valence electrons.

Shielding Effect

The lessening of attractive electrostatic charge difference between nuclear protons ang valence electrons by partially or fully filled inner shells.

Ionization Energy

The amount of energy required to remove an electron from an atom

Electron Affinity (EA)

The energy that an atom releases when it accepts an electron

Atomic Radius

Periodic Trends that Decreases from Left to Right, Increases from Top to Bottom

Ionization Energy, Electron Affinity, Electronegativity

Periodic Trends that Increases from Left to Right, Decreases from Top to Bottom

Ionic Compounds

Metal and Non-Metal Elements

Covalent Compounds

Both Non-Metal Elements

Mettalic Compounds

Both Metal

Polar

Electrons attracted to elements with higher electronegativity

Ex:

F and Li, the electrons will be attracted to Fluorine

Non-Polar

Electrons are shared equally

Ex:

O and S, electrons are equally distributed because they’re in the same group

Single Bond, Double Bond, Triple Bond

TYPES OF BONDS

Resonance

More than one bond is formed in the Lewis Structure

Ex:

CH3Cl - A ____

CH - Not a ____

Electronegativity

The ability of an atom in a chemical bond to attract electrons towards itself