CHEM 1st Exam Vocab

Electromagnetic Radiation

Any form of radiant energy in the electromagnetic spectrum

Electromagnetic Spectrum

The range of radiant energy includes gamma rays, X-rays, ultraviolet radiation, visible light, infrared radiation, microwaves, and radio waves

Wavelength (λ)

Distance between successive peaks of a wave.

Frequency (ν)

Number of wave cycles per second.

Hertz (Hz)

Unit of measurement for frequency (1 s^-1)

Speed of light (c)

3.00 x 10^8 m/s

Fraunhofer lines

A set of dark lines in the otherwise continuous solar spectrum.

Atomic Emission Spectra

Characteristic patterns of bright lines are produced when atoms are vaporized in high-temperature flames or electrical discharge

Atomic Absorption Spectra

Characteristic patterns of dark lines are produced when an external source of radiation passes through gaseous atoms

Quantum

The smallest discrete quantity of a particular form of energy (E=hv)

Photon

A quantum of electromagnetic radiation

Photoelectric Effect

The emission of electrons from a material when light of certain frequencies shines on the surface of the material

Threshold Frequency

the minimum frequency of light required to produce the photoelectric effect

Excited State

An energy level above the ground state

Electron Transitions

movement of an electron between energy levels

Quantum Numbers

specify the properties of atomic orbitals and the properties of electrons in orbitals

n (principle quantum #)

Energy level(distance from nucleus)

Any integer 1-infinity

l (angular momentum #)

specifies the general shape of the orbitals. Possible values are 0...(n-1)

Magnetic Quantum Number (ml)

Specifies the orientation in space of the orbital. Possible values depend on l, can be -l to +l in steps of one.

ms (spin quantum #)

Electron's spin (up/down)

+1/2 or -1/2

Shell

Described only use n

Subshell

Described only using n & l

Orbital

Described using n, l, & ml

Pauli Exclusion Principle

An atomic orbital may describe at most two electrons, each with opposite spin direction

Hund's Rule

orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin

Exceptions to Electron Configuration

Cr, Mo, Cu, Ag, Au (Missing an electron in their s orbital to complete their d orbital)

Ionization Energy

The amount of energy required to remove an electron from an atom

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons

Atomic Radius

size of an atom

Ionic Radius

Distance from the center of an ion's nucleus to its outermost electron

Ionic Bond

Formed when one or more electrons are transferred from one atom to another. Metals & nonmetals (lattice)

Covalent Bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule. Nonmetal & nonmetal/metalloids

Metallic

metal and metal

Polyatomic Ions

Covalent molecules w/ extra/fewer e- to make them ions

Acetane

C2H3O2-/CH3COO-

Hydroxide

OH-

Cyanide

CN-

Ammonium

NH4+

Oxyanion

a polyatomic ion composed of an element, usually a nonmetal, bonded to one or more oxygen atoms

Carbonate

CO3 2-

Chlorate

ClO3-

Nitrate

NO3-

Phosphate

PO4 3-

Sulfate

SO4 2-

Binary Covalent Molecules Naming Conventions

Prefix (omit mono if just 1)-1st element prefix-2nd element-ide

Acids

A covalent molecule that produces H+ (proton) when dissolved in water

Binary Acids Naming conventions

A single non-metal w/ H+

hydro-2nd element-ic acid

Oxyacids Naming Conventions

Oxyanions w/ H+

If an oxyanion ends in "ate" --> "-ic acid"

If an oxyanion ends in "ite" --> "ous acid"