Name:______Hour:______

Guided Notes
Chapter 5

The Bohr Model

  • Bohr proposed that an electron is found only in ______or orbits around the nucleus.
  • Each possible electron orbit has a fixed energy called an ______.

Energy Levels

  • Fixed energy levels of electrons are similar to rungs of a______.
  • The lowest possible energy level is called its ______.
  • Just like a person an electron can ______from one rung (energy level) to another. It ______be found in between rungs (energy levels).
  • To move from one level to another an electrons must ______or ______energy.

Quantum

  • Amount of energy required to move an electron from one energy level to another.
  • The amount of energy an electron gains or loses in an atom is not always the ______.
  • The ______energy levels are ______together so it takes less energy to move between levels

Quantum Mechanical Model

  • ______
  • Determines energies of an electrons
  • Electron location is based on how likely it can be found at a particular location.

Label the model:

Atomic Orbitals

  • Region of space in which there is a ______of finding an electron
  • Energy levels are labeled by numbers, n= 1, 2, 3, 4, 5, 6 or 7
  • Each energy level has ______
  • Orbitals are labeled by letters and different letters have different shapes

Summary of Principal Energy Levels, Sublevels, and Orbitals

Principal Energy level / Number of sublevels / Type of sublevel

Maximum number of electrons

  • n = 1 : ____ electrons
  • n = 2 : ____ electrons
  • n = 3 : ____ electrons
  • n = 4 : ____ electrons

Electron Configuration:

  • Arrangement of electrons in orbitals around the nucleus of an atom
  • 3 rules govern the arrangement:
  • Aufbau principle
  • Pauli exclusion principle
  • Hund’s rule

Aufbau Principle

  • Electrons enter the ______energy level first.

Pauli Exclusion Principle

  • An orbital can hold at most 2 electrons, if 2 electrons are present they must have opposite spins
  • An up or down arrow indicates the electron’s spin ↑ or ↓,
  • An orbital with paired electrons is written as

Hund’s Rule

  • One electron into each orbital until all orbitals have 1, then the second one can enter.

Electron Configuration

Element / 1s / 2s / 2px / 2py / 2pz / 3s / Electron Configuration
H
Li
O
F
Ne
Na

Exceptional Electron Configuration

  • There are always exceptions to the rules
  • Cr : 1s2 2s2 2p6 3s2 3p6 3d5 4s1
  • Cu :1s2 2s2 2p6 3s2 3p6 3d10 4s1
  • Exceptions due to subtle electron interactions in orbitals with similar energies

Light

  • The study of light led to the quantum mechanical model
  • Newton stated: light consists of particles
  • Huygens stated: light travels in waves
  • Formula:
  • C = λ ν
  • Speed of light (C)
  • Wavelength (λ)
  • Frequency (ν)

Electromagnetic Spectrum

  • The arrangement of types of radiation from long wavelengths to short wavelengths
  1. What color in the visible spectrum has the longest wavelength? ______
  2. Which color in the visible spectrum has the highest energy? ______

Calculation

Problem: Underline the givens in the problem

Calculate the wavelength of the yellow light emitted by a sodium lamp if the frequency of the radiation is 5.10 x 1014 Hz (5.10 x 1014 /s) and the speed of light is 3.00 x 108 m/s.

Step One: Write the Given

Step Two: Write the Equation

Step Three: Substitute in your given(s)

Step Four: Solve

Problem: Try this one on your own. I will come around to check.

Calculate the wavelength of the purple light emitted by a potassium lamp if the wavelength of the radiation is 4.047 x 10-7 m and the speed of light is 3.00 x 108 m/s.

Atomic Spectra

  • When atoms absorb energy electrons move to higher energy levels these electrons then lose energy by emitting light when they return to the lower energy level
  • Each discrete line in an emission spectrum correspond to 1 exact frequency of light emitted by the atom.
  • Formula:
  • E = h ν
  • Energy (E)
  • Plank’s constant (h)
  • Frequency (v)

Quantum Mechanics

Photoelectric effect

  • Einstein used Newton idea’s said light could be described as quanta of energy that behave as particles
  • Light quanta  photons

Atomic Spectra

  • The motions of subatomic particles and atoms as waves

Chapter 6

How did chemists begin to organize the known elements?

  • Chemists used the properties of elements to sort them into groups
  • Chlorine, bromine and iodine have very similar properties

Mendeleev’s Periodic Table

  • He arranged the elements in his periodic table in order of ______atomic mass.
  • The periodic table can be used to predict the properties of undiscovered elements

Modern Periodic Table Arrangement

  • Elements are arranged in order of increasing ______

Periodic Law

  1. ______
  2. There is repeating pattern of their physical and chemical properties
  3. The properties of an element within a period change as you move from left to right
  4. The pattern of properties within a period repeats as you move from one period to the next.

There are 3 broad classes of elements:

  1. Metals
  2. Nonmetals
  3. ______

Metals:

  • Good conductors
  • ______
  • High luster, ductile & malleable

Non-Metals:

  • ______
  • Dull and brittle
  • Most are gases at room temperature

Metalloids:

  • ______
  • Behavior can be controlled by changing

conditions

Identify the following elements as metals, nonmetals, or metalloids:

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Name:______Hour:______

  1. Carbon (C ) ______
  2. Boron (B) ______
  3. Calcium (Ca) ______
  4. Barium (Ba) ______
  5. Copper (Cu) ______
  6. Bromine (Br) ______
  7. Neon (Ne) ______
  8. Silicon (Si) ______
  9. Iodine (I) ______

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Name:______Hour:______

Rows and periods:

  • Horizontal rows are called periods. Periods indicates the number of occupied electron shells
  • Vertical columns are called families or groups (elements have similar properties)
  • The background colors in the squares are used to distinguish groups of elements
  • Group 1A: alkali metals
  • Group 2A: alkaline earth metals
  • Group 7A: halogens

Elements are arranged in families based on electron configuration:

  • Noble Gases: Elements in group 8A
  • Representative Elements: Elements in groups 1A – 7A
  • Transition Elements:Elements in Group B in main part of periodic table
  • Inner transition metals:The elements below the main body of the periodic table

Noble Gases

  • Noble gases are elements in Group 8A
  • The highest energy level is filled.

Element (Symbol) / Written Electron Configuration

The Representative Element:

  • Elements in groups 1A through 7A are often referred to as representative elements because they display a wide range of physical and chemical properties.
  • The s and p sublevels of the highest occupied energy level are not filled
  • The group number equals the number of electrons in the highest occupied energy level

Group 1A: one electron in the highest occupied energy level

Element (Symbol) / Written Electron Configuration

Group 4A: four elements in the highest occupied energy level

Element (Symbol) / Written Electron Configuration

Transition Elements:

  • There are two types of transition elements – transitions metals and inner transition metals.
  • They are classified based on their electron configurations
  • In atoms of a transition metal, the highest occupied s sublevel and nearby d sublevel contain electrons
  • In atoms of an inner transition metal, the highest occupied s sublevel and a nearby f sublevel generally contain electrons

Atomic Size

  • The atomic radius is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined.
  • In general, atomic size increases from top to bottom within a group and decreases from left to right across a period.

Draw arrows
indicating the
trend:

Ions

  • During reactions between metals and nonmetals, metal ions tend to lose electrons and nonmetals tend to gain electron
  • ______are positive ions, they lose electrons
  • ______are negative ions and they gain electrons

Ionic Size

  • Cations are smaller than the atoms and anions are larger than the atoms
  • In general, ionic size of cations and anions decrease from left to right across periods and increase from top to bottom within groups.

Draw arrows
indicating the
trend:

Ionization Energy

  • Ionization energy is the energy required to ______an electron from an atom.
  • In general the ionization energy tends to increase from left to right across a period and decrease from top to bottom within a group.

Draw arrows
indicating the
trend:

Electron Affinity

  • The energy change involved when a electron is added to a gaseous atom
  • In general, the electron affinity increases from left to right across a period and decrease from top to bottom within a group.

Draw arrows
indicating the
trend:

Electronegativity

  • Electronegativity is the ability of an atom to attract electrons to itself when bonded to another atom
  • In general, electronegativity decreases for top to bottom within a group and increase from left to right

Draw arrows
indicating the
trend

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