Unit 05 - Electrons in Atoms

the test being tomorrow the day I come back is crazy

Electromagnetic Radiation

Form of energy that exhibits wavelike behaviour as it travels through space

Radiant Energy

Energy that travels in the form of waves; both electrical and magnetic properties

EM Spectrum

Whole range of EM radiation

Frequency

The number of occurrences of a repeating event per unit of time

Wavelength

The distance over which the wave's shape repeats

3.00 × 10⁸ m/s

Speed of light (c) = ___

wavelength

The lower the frequency, the higher the ___.

frequency

The lower the wavelength, the higher the ___.

1km-1cm

Radio Waves

0.1cm-1mm

Microwaves

1mm-1hm

Infrared (IR) Waves

1hm-100nm

Visible Waves

100nm-10nm

Ultraviolet (UV) Waves

10nm-0.001nm

X-Rays

0.001nm-0.00001nm

Gamma (y) Rays

E = hv

Energy equation for finding photons in waves

6.626 × 10^-34 J*s

Planck’s constant (h)

Niels Bohr

Proposed that electrons must have enough energy to keep them in constant motion around the nucleus

Planetary Model

• All + charge and mass in nucleus

• Electrons circle the nucleus in circular paths

Orbitals

__ are circular paths around atoms. They are defined with the quantum number n and can only be whole numbers and start at 1. They are regions of space in which electrons can move freely about the nucleus of an atom. More Specific.

n=1

<=2 electrons

n=2

<=8 electrons

n=3

<=18 electrons

Ground State

When electrons are in their lowest energy orbitals

Excited State

When energy is added to electrons, and they absorb it & jump to the next energy orbital

Emission

Excited → Ground. Energy released. e.g: visible light

emission spectrum

Range of light released from excited atoms of an element is called the __ of that element

Energy Levels

Fixed distances around the nucleus where an electron is likely to be found.

Electron Clouds

Space around the nucleus where electrons are most-likely found. More Broad.

speed of light (3.00 × 10^8 m/s)

Electrons move at the __ (__).

Aufbau Principle

Electrons occupy the lowest energy orbitals available

Pauli Exclusion Principle

A maximum of two electrons can occupy a single atomic orbital; electrons spin opposite directions.

Hund’s Rule

Single electrons with the same spin must occupy each equal-energy orbital before more electrons with opposite spins can occupy the same orbitals that these electrons are on; basically, all electrons in one orbital must have the same spin before other electrons with opposite spin can join in that orbital.

Valence electrons

Electrons in the outmost energy levels

Groups

Columns in the periodic table

Periods

Rows in the periodic table

G3-G12

Groups with 0 valence electrons

Electron Dot Diagram; 1 electron; 1 energy level; 1 orbital; 1 valence electrons; 1 possible bond

Diagram name; # of electrons; # of energy levels; # of orbitals; # of valence electrons; # of possible bonds