Chemistry Chapter 5

Electromagnetic radiation

a form of energy that exhibits wavelike behavior as it travels through space

Wavelength

the shortest distance between 2 equivalent points on a continuous wave

Units for wavelength

meter or nanometer

Symbol for wavelength

lambda, λ

Frequency

the number of waves that pass a given point per second

Unit for frequency

hertz, 1/s

Symbol for frequency

nu, ν

Amplitude

the wave's height from the origin to a crest or trough

Speed of light equation

c (speed of light, m/s) = λ (wavelength, m or nm) * ν (frequency, hertz)

inversely

Wavelength and frequency vary ________.

Electromagnetic spectrum

a spectrum that includes all forms of electromagnetic radiation

Quantum theory

a theory created by Max Planck to explain how matter lost and gained only small, specific amounts of energy

Quantum

the minimum amount of energy that can be lost or gained or gained by an atom

Photon

a particle-like bundle of energy without mass that carries a quantum of electromagnetic energy

Energy of a photon equation

E (energy, joules) = h (Planck's constant, joules * seconds) * ν (frequency, hertz)

Spectroscopy

the method of studying substances exposed to energy

Spectrum

the pattern of energy studied in spectroscopy

Atomic emission spectrum

the set of frequencies or wavelengths of the electromagnetic waves emitted by atoms of the element

unique

Each element produces a ________ line spectrum.

Bohr's (planetary) model

an early atomic model of the hydrogen atom that was developed by studying the emission spectrum of hydrogen

Accurate part of Bohr's model

the electron can only posses certain quantities of energy/ have certain allowed energy states

Ground state

the lowest and most stable energy state

Excited state

any state of energy that is more than the lowest amount

Inaccurate part of Bohr's model

the electron moves around the nucleus in certain allowed circular orbits

waves

Electrons should be thought of as ________ spread out in space. (Louis de Broglie)

measurement

The act of ________ disturbs the object being measured.

Heisenberg uncertainty principle

states that it is fundamentally impossible to know precisely both the velocity and position of a particle at the same time

Quantum mechanical model

modern atomic model, a mathematical equation that treated an electron as a wave and solved the equation for the hydrogen atom

Lowest energy level

1

farther

The ________ the electron, the higher the energy level

Energy sublevel

a subdivision of an energy level, assigned a letter: s, p, d, or f

Atomic orbital

the volume around the nucleus in which the electron is likely to be found

Sublevel "s"

spherical, 1 orientation

Sublevel "p"

dumbbell, 3 orientations

Sublevel "d"

cloverleaf, 4 orientations, dumbbell with donut, 1 orientation (5 orientations in total)

Sublevel "f"

7 different orientations

larger

The orbitals in the higher energy levels are ________ than the orbitals in the lower energy levels

Max electrons in "s"

2

Max electrons in "p"

6

Max electrons in "d"

10

Max electrons in "f"

14

Electron configuration

a notation for showing how electrons are arranged in energy sublevels

2

How many electrons can be in a sublevel

Aufbau principle

sublevels are "filled" with electrons starting with the lowest energy sublevel

Quantum numbers

a set of four numbers used to describe the properties in electrons in an atom

Pauli exclusion principle

states that each electron in an atom has a unique set of 4 quantum numbers and that 2 electrons can be in an orbital only if they have opposite spins

Abbreviated electron configuration

noble gas in brackets and portion of configuration that remains

Orbital diagram

notation used to depict electrons in orbitals

Hund's rule

the most stable arrangement of electrons within a sublevel is one with greatest number of parallel spins

Degenerate

electrons with the same amount of energy

Electron dot diagram/ Lewis dot structure

notation used tp symbolize atom's valence electrons

Valence electron

the electrons in the outermost (largest) orbitals, determine element's properties