chemistry unit 3 assessment

Ground state

The lowest energy electronic configuration possible for an atom.

Excited state

Any electronic state of an atom that has higher energy than its lowest possible energy state.

Relationship between wavelength and energy

Inversely proportional; as wavelength decreases, photon energy increases.

Principal quantum number ($n$)

how far an e- is from nucleus

where $n$ is a positive integer ($1, 2, 3, \dots$).

Secondary quantum number ($l$) or azimuthal

energy and shape of the orbital,

integer values ranging from $0$ to $n - 1$.

Magnetic quantum number ($m_l$)

orientation of an orbital

integer values from $-l$ to $+l$.

Spin quantum number ($m_s$)

spin state of an electron

values of $+\frac{1}{2}$ or $-\frac{1}{2}$.

Subshell corresponding to $l = 0$

$s$ subshell

spherical shape

contains $1$ orbital, and holds up to $2$ electrons.

Subshell corresponding to $l = 1$

The $p$ subshell,

dumbbell-shaped orbitals

contains $3$ orbitals, and holds up to $6$ electrons.

Subshell corresponding to $l = 2$

The $d$ subshell,

$5$ orbitals and holds up to $10$ electrons.

subshell corresponding to l=3

f subshell

Aufbau principle

Rule stating that electrons occupy the lowest-energy available orbitals before filling higher-energy ones.

Hund's rule

Rule stating that degenerate orbitals are each occupied by one electron with parallel spins before any orbital is doubly occupied. (point up before down)

Pauli exclusion principle

Principle stating that no two electrons in an atom can have the same set of four quantum numbers.

Periodic trend for atomic radius

Increases down a group and decreases across a period from left to right.

Ionization energy

energy needed to remove an electron from a neutral gaseous atom or ion.

loses e-

positive/ cation

endothermic (needs energy)

Electron affinity

energy released when electron is added to a neutral atom in the gaseous state.

GAINS e-

anion / negative

exothermic & endothermic

frequency/wavelength formula

V= λ•C or λ= V/c or λV=c

explain what happens on the left side

shorter wavelength

higher frequency

higher energy

what happens to the right of this

longer wavelength

shorter frequency

shorter energy

finding energy formula

E = nhc/λ

where can electrons exist on

only e levels

what does an electron absorbs a photon mean

atom gains an e- / moving up

what does an electron emits a photon mean

atom loses an e- / moving down

formula for finding wavelength using energy

λ=hc/E

formula for finding energy released IN A HYDROGEN ATOM

2.18×10^-18 J (1/ni² -1/nf²)

how many e- can an orbital hold

2

being in the same periodic table row means what (side to side) (horizontal)

same # of e- shells

larger atomic radius means what

smaller nuclear change

smaller atomic radius means what

larger nuclear change

nano means what

x 10 -9

more protons means what

stronger & smaller

reactivity trend

increasing horizontally decreasing vertically

GHz is what

x 10^9