Chapter 6Electronic Structure

and the Periodic Table

c= λf• λ = c/f• f = c/λ

c = speed of light, 2.998 x 108m/sλ = wavelength, mf = frequency, Hertz, Hz

ProblemMicrowaves have a wavelength of 1.000 cm.

Calculate their frequency in Hz.1.000 cm = 1.000 x 10-2mf = (2.998 x 108m/s)/1.000 x 10-2m = 2.998 x

1010Hz

ProblemCalculate the wavelength of a band on your AM

radio with a frequency of 4.56 x 105Hz. λ = (2.998 x 108m/s)/(4.56 x 105Hz) = 657 m

Wave

EnergyE = hc/λ

E = hf

E = energy, Joules, Jc = speed of sound, 2.998 x 108m/sh = Planck’s constant, 6.626 x 10-34J*s

ProblemCalculate the the energy of microwaves in Joules, using the frequency 2.998 x 1010Hz.

E = hf

E = (6.626 x 10-34J*s)(2.998 x 1010Hz) = 1.986 x 10-23J

ProblemCalculate the energy in Joules of an AM radio wave having a wavelength of 657 m.

E = hc/λ

E = (6.626 x 10-34J*s)(2.998 x 108m/s)/657 m = 3.0 x 10-28J

Quantum Numbers

Principle Quantum Number

Symbolized by n

Indicates the main energy level occupied by the electron

Values are integers starting with 1

Angular Momentum Quantum Number

Symbolized by l

Indicates shape

Values are 0, 1, 2, 3

s p d f

0 1 2 3

Magnetic Quantum Number

Symbolized by ml

Indicates the orientation of the orbital around the nucleus

Values are l,…, +1, 0, -1, ..., -l

Spin Quantum Number

Symbolized by ms

Indicates the fundamental spin states of an electron in an orbital

Values are + ½ and -1/2

ReviewElectron ConfigurationsOrbital DiagramsNoble Gas ConfigurationsPeriodic trends

Atomic RadiusIonization EnergyElectronegativty

Periodic TrendsAtomic Radius

Decreases across periodic table from left to right

Increases down a groupIonization Energy

Increases across periodic table from left to rightDecreases down a group

ElectronegativityIncreases across periodic table from left to

rightDecreases down a group

Ionic RadiusIonic Radii increase down a group.Cations are smaller than their corresponding atoms.Anions are larger than their corresponding atoms.

Chapter 6 Assignment

Summary problem page 158

Chapter Review p. 1592, 5, 10, 30, 32, 34, 34, 38, 40