CH 301 - Unit 1

This set has information added on after each lesson. (Current: 1.21)

Wavelength

distance between peaks

frequency

number of waves that pass by in an allotted time

short peak distances mean

a short wavelength

long peak distances mean

a long wavelength

When two wavelengths travel at the same speed, the shorter wavelength

will have a higher frequency.

Speed of Light constant

3.00 × 10⁸ m/s

Speed of Light formula

C=wavelength x frequency

Energy formula

Energy=planck’s constant x frequency

Combined Energy & Speed of Light formula

E=(Planck’s constant x speed of light)/ frequency

Electromagnetic Spectrum - 1

radiowave

Electromagnetic Spectrum - 2

microwave

Electromagnetic Spectrum - 3

infrared

Electromagnetic Spectrum - 4

visible light

Electromagnetic Spectrum - 5

UV - Rays

Electromagnetic Spectrum - 6

X-ray

Electromagnetic Spectrum - 7

Gamma

Visible light wavelength (nm)

300-700nm

Color Scale (longest to shortest)

red → orange → yellow → green → blue → purple

Light is like a tiny particle or wave called a

photon!

Increasing brightness only increases the

number of photons emitted

Increasing energy only increases the

likelihood that a photon will be emitted

Lowering the work function

allows for a higher chance there will be a photon emitted

If the e-photon is greater than the work function, then

there will be an electron ejected.

If the e-photon is lesser than the work function, then

there will NOT be an electron ejected.

electron kinetic energy formula

Ek = (Planck’s constant x frequency) - work function

E-photon formula

Planck’s constant x frequency

Radiowaves will

excite the spin of a nucleus

Microwaves will

excite the spin of electrons

Infrared-waves will

cause vibration of molecules

Visible and UV light will

excite valence electrons

X-rays will

excite core electrons

Gamma Rays will

be associated with decay of nucleus

Bohr’s model states that

electrons orbit the nucleus.

Is Bohr’s model correct?

No, but it allows for the foundation of electron rings.

When one moves AWAY from the nucleus, the energy

increases.

As one moves AWAY from the nucleus, the gaps between rings will

become smaller.

Going from low to high rings indicates

absorption. (allows for colors to be seen)

Going from high to low rings indicates

emission.

Rydberg equation

frequency = R x ([low]1/n² - [high]1/n²)

Rydberg constant

3.3 × 10¹⁵

The Rydberg equation only applies to

hydrogen

de Brolie states that

objects with mass can acts as a wave

de Brolie equation

wavelength = Planck’s constant/ (mass x velocity)

Experimentally, electrons move as

waves

The de Brolie equation led to the development of the

electron microscope.

The quantum numbers model tells us if

there is a chance of finding an electron.

Principle QN

describe the energy level of an electron inside an atom

Angular momentum QN

describes the shape of the subshell

When (n=1), “L” will be

0

When (n=2), “L” will be

1

When (n=3), “L” will be

2

When (n=4), “L” will be

3

Magnetic QN

describes the orbital within a subshell

When “L” is 0, “ML” will be

0

When “L” is 1, “ML” will be

-1, 0, 1

When “L” is 2, “ML” will be

-2, -1, 0, 1, 2

When “L” is 3, “ML” will be

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

Electron Spin (ms)

depicts which way the electrons are spinning

ms = ½

spinning up

ms = - ½

spinning down

1st step of electron configuration

find number of electrons in an element

2nd step of electron configuration

fill in Aufbau’s boxes depending on the number of electrons

It takes energy to pair electrons, so

fill boxes unpaired first.

S- Group can hold

2 electrons

P - Group can hold

6 electrons

D - Group can hold

10 electrons

Anion (-) is the addition of electrons to the

next available orbital

Cation (+) is the removal of electrons from the

highest (n) value

D - block exception prefers to

be half-filled and filled

Ionization energy refers to

the amount of energy it takes to remove an electron from an atom in the gas stage.

A small distance between the proton to the core electrons indicates a

strong attraction

A large distance between the proton to the core electrons indicates a

weak attraction

A strong attraction indicates

a higher IE to break

A weaker attraction indicates

a lower IE to break

Equation for Zeff

number of protons - core electrons

Lower Zeff indicates

lower IE

If it is in the same shell and has the same Zeff,

look at valence electrons to see if they repel.

Repelling allows for

less effort to remove electrons.