Electrons in Atoms Chap. 5

Light (electromagnetic radiation)

Light (electromagnetic radiation) A. Two components

Light (electromagnetic radiation) A. Two components Electrical wave

Light (electromagnetic radiation) A. Two components Electrical wave Magnetic wave

Light (electromagnetic radiation) A. Two components B. Two natures

Light (electromagnetic radiation) A. Two components B. Two natures Particle

Light (electromagnetic radiation) A. Two components B. Two natures Particle Wave

Light Characteristics of a Light Wave

Light Characteristics of a Light Wave wavelength

Light Characteristics of a Light Wave wavelength The distance between successive wave crests

Light Characteristics of a Light Wave wavelength frequency The time it takes a wave to pass a given point

Light Characteristics of a Light Wave wavelength frequency amplitude The height of a wave

Light Characteristics of a Light Wave wavelength frequency amplitude speed

Light Characteristics of a Light Wave The Wave Equation

Light Characteristics of a Light Wave The Wave Equation inverse relation of wavelength and frequency

Light Characteristics of a Light Wave The Wave Equation inverse relation of wavelength and frequency check the units

The Wave Equation c = λ x υ

Self Check – Ex. 1 A light wave has a frequency of 2.6 x 1014 Hz. What is the wavelength?

Self Check – Ex. 2 What is the frequency of light with a wavelength of 0.0000072 m?

Light Characteristics of a Light Wave The Wave Equation Planck’s Equation

Planck’s Equation E = h x υ h = 6.63 x 10-34 J·s

Self Check – Ex. 3 A light photon has 4.2 x 10-19 J of energy. What is the frequency of this light?

Self Check – Ex. 4 How much energy does a photon of orange light have (λ = 630 nm)? 109 nm = 1 m

Light Characteristics of a Light Wave The Wave Equation Planck’s Equation The Electromagnetic Spectrum

Electromagnetic Spectrum Long waves Short waves

Electromagnetic Spectrum Long waves Short waves Radio waves

Electromagnetic Spectrum Long waves Short waves Radio waves Micro-waves

Electromagnetic Spectrum Long waves Short waves Radio waves Infra-red Micro-waves

Electromagnetic Spectrum Long waves Short waves Radio waves Infra-red Micro-waves Visible

Electromagnetic Spectrum Long waves Short waves Radio waves Infra-red Ultra-violet Micro-waves Visible

Electromagnetic Spectrum Long waves Short waves Radio waves Infra-red Ultra-violet Micro-waves Visible X-rays

Electromagnetic Spectrum Long waves Short waves Radio waves Infra-red Ultra-violet Gamma rays Micro-waves Visible X-rays

Emission Spectra

Emission Spectra Definition

The various types of light given off when an atom is excited Emission Spectrum: The various types of light given off when an atom is excited

Emission Spectra Definition Examples

Hydrogen’s Spectrum Note – only a few colors are present 400 nm 500 nm

Mercury’s Spectrum 400 nm 500 nm 600 nm 700 nm

Neon’s Spectrum 400 nm 500 nm 600 nm 700 nm

Emission Spectra Definition Examples Explanation – Bohr’s Model

Bohr’s Model of an Atom e-

Bohr’s Model of an Atom e- Electrons orbit the nucleus (like planets orbiting the sun) e-

Bohr’s Model of an Atom e- Electrons must be in a specific orbit (never between orbits) e- n=1 n=2 n=3

Bohr’s Model of an Atom e- Electron wants to be in the lowest unoccupied level e-

Bohr’s Model of an Atom e- The energy of the electrons depends on the distance from the nucleus e- high energy low energy

Bohr’s Model of an Atom e- Light is emitted when electrons fall to lower energy levels e-

Bohr’s Model of an Atom Only certain sized falls are permitted. e-

Hydrogen’s Spectrum What is the energy for each line produced? Color 410 nm 486 nm 656 nm 434 nm Color Wavelength Frequency Energy Red 6.56x10-7 m Green 4.86x10-7 m Blue 4.34x10-7 m Purple 4.10x10-7 m

Hydrogen’s Spectrum What is the energy for each line produced? Color 410 nm 486 nm 656 nm 434 nm Color Wavelength Frequency Energy Red 6.56x10-7 m 4.57x1014 Hz Green 4.86x10-7 m 6.17x1014 Hz Blue 4.34x10-7 m 6.91x1014 Hz Purple 4.10x10-7 m 7.32x1014 Hz

Hydrogen’s Spectrum What is the energy for each line produced? Color 410 nm 486 nm 656 nm 434 nm Color Wavelength Frequency Energy Red 6.56x10-7 m 4.57x1014 Hz 3.03x10-19 J Green 4.86x10-7 m 6.17x1014 Hz 4.09x10-19 J Blue 4.34x10-7 m 6.91x1014 Hz 4.58x10-19 J Purple 4.10x10-7 m 7.32x1014 Hz 4.85x10-19 J

III. A new model

III. A new model A. Quantum Mechanics Electrons’ location cannot be accurately determined

III. A new model A. Quantum Mechanics 1. Orbitals

Orbital A region of space around the nucleus where an electron is likely to be found.

Types of Orbitals s orbital

Types of Orbitals s orbital p orbitals

Types of Orbitals s orbital p orbitals d orbitals

Types of Orbitals s orbital p orbitals d orbitals f orbitals

III. A new model A. Quantum Mechanics Orbitals Sublevels

Sub-level A group of orbitals that have the same shape and energy.

III. A new model A. Quantum Mechanics Orbitals Sublevels A few examples

III. A new model A. Quantum Mechanics Orbitals Sublevels A few examples Their electron capacity

Sublevels Capacity Each orbital can hold 2 electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds ___ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds ___ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds _6_ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds _6_ electrons A ‘d’ sublevel is made of FIVE orbitals, so it holds ____ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds _6_ electrons A ‘d’ sublevel is made of FIVE orbitals, so it holds _10_ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds _6_ electrons A ‘d’ sublevel is made of FIVE orbitals, so it holds _10_ electrons An ‘f’ sublevel is made of SEVEN orbitals, so it holds ____ electrons

Sublevels Capacity Each orbital can hold 2 electrons An ‘s’ sublevel is made of ONE orbital, so it holds _2_ electrons A ‘p’ sublevel is made of THREE orbitals, so it holds _6_ electrons A ‘d’ sublevel is made of FIVE orbitals, so it holds _10_ electrons An ‘f’ sublevel is made of SEVEN orbitals, so it holds _14_ electrons

III. A new model A. Quantum Mechanics Orbitals Sublevels A few examples Their electron capacity The ordered list

III. A new model B. Arrangement of electrons

III. A new model B. Arrangement of electrons Aufbau principle Electrons fill the lowest energy level first.

III. A new model B. Arrangement of electrons Aufbau principle Pauli Exclusion Principle Two electrons per orbital with opposite spin

III. A new model B. Arrangement of electrons Aufbau principle Pauli Exclusion Principle Hund’s Rule Half fill all orbitals in a sublevel before completely filling them

III. A new model B. Arrangement of electrons Aufbau principle Pauli Exclusion Principle Hund’s Rule A pictorial representation ‘The Aufbau Hotel’

IV. Orbital Diagrams A representation of the electrons in an atom

IV. Orbital Diagrams Boxes represent . . .

IV. Orbital Diagrams Boxes represent . . . An ‘f’ sublevel should have 7 boxes

IV. Orbital Diagrams Boxes represent . . . An ‘f’ sublevel should have 7 boxes ‘d’ = 5 boxes

IV. Orbital Diagrams Boxes represent . . . An ‘f’ sublevel should have 7 boxes ‘d’ = 5 boxes ‘p’ = 3 boxes

IV. Orbital Diagrams Boxes represent . . . An ‘f’ sublevel should have 7 boxes ‘d’ = 5 boxes ‘p’ = 3 boxes ‘s’ = 1 box

IV. Orbital Diagrams Boxes represent . . . Arrows represent . . .

IV. Orbital Diagrams Boxes represent . . . Arrows represent . . . These boxes are filled in a specific order See Aufbau, Pauli Exclusion, and Hund above

Self Check – Ex. 5 Write the orbital diagrams for: Fluorine Vanadium Germanium

V. Electron Configuration A shorthand notation of electron positions in an atom

V. Electron Configuration Number represents energy level

V. Electron Configuration Number represents energy level Letter shows the type of sublevel

V. Electron Configuration Number represents energy level Letter shows the type of sublevel Electrons are counted and written as an exponent

V. Electron Configuration The ordered list

V. Electron Configuration The ordered list 1s22s22p63s23p64s23d104p65s24d105p66s24f145d106p67s25f146d107p6

Self Check – Ex. 6 Write the electron configurations for: Magnesium Sulfur Silver

VI. Electron Config. using P.T.

VI. Electron Config. using P.T. The s-block

VI. Electron Config. using P.T. The s-block The p-block

VI. Electron Config. using P.T. The s-block The p-block The d-block

VI. Electron Config. using P.T. The s-block The p-block The d-block The f-block

VI. Electron Config. using P.T. The s-block The p-block The d-block The f-block The order of sublevels (made easy!)

Self Check – Ex. 7 Use your P.T. to write electron configurations for: Potassium Arsenic Rhodium

VII. Electron Config. using abbreviations

VII. Electron Config. using abbreviations Abbreviate the previous noble gas in brackets

VII. Electron Config. using abbreviations Abbreviate the previous noble gas in brackets Write configuration of remaining electrons

Self Check – Ex. 8 Write the abbreviated electron configurations for: Iridium Terbium Radon

VII. Exceptions to Aufbau

VII. Exceptions to Aufbau Copper 1s22s22p63s23p64s13d9

VII. Exceptions to Aufbau Copper Chromium 1s22s22p63s23p64s13d5

VII. Exceptions to Aufbau Copper Chromium There are others

IX. Lewis Dot Diagrams A diagram that uses dots to represent valence electrons

IX. Lewis Dot Diagrams Valence electron

IX. Lewis Dot Diagrams Valence electron The outermost electrons (the ones that bond)

IX. Lewis Dot Diagrams Valence electron The outermost electrons (the ones that bond) Determined by adding the highest energy s and p electrons

Self Check – Ex. 9 How many valence electrons do the following have? Nitrogen Arsenic Chlorine

IX. Lewis Dot Diagrams Valence electron We write these for representative elements Representative elements are found in the ‘s’ and ‘p’ blocks

Self Check – Ex. 5 Write Lewis structures for: Strontium Iodine 1s22s22p63s23p64s23d104p65s24d105p3

The End