Chemistry Exam 4 Flashcards

Wavelength (λ)

Distance between two successive crests or troughs (units: m or nm)

Frequency (v (“nu”))

Number of crests that pass a point in a certain time (units: s^-1 or hertz)

c = λv

Equation for velocity of light

frequency (v), wavelength (λ)

Energy (E) is proportional to _, and inversely proportional to _

E = hv

Equation for energy

Ground state

System at lowest energy

Excited state

System at highest energy

ΔE = -R_H (1/n_f² - 1/n_i²)

Equation for energy absorbed or emitted (ΔE)

λ = h/mu (u = velocity)

DeBrogolie Equation calculating the wavelength of a moving particle

Quantum numbers

Numbers that describe atomic orbitals

Principal Quantum Number (n)

Number that indicates the size and energy level of atomic orbitals. It is always assigned a positive integer value (e.g., n = 1, 2, 3...)

Angular Momentum Quantum Number (l)

The quantum number that describes the shape of an electron's orbital and can range from 0 to n-1 (value designated with a letter - s, p, d, f, g)

Magnetic Quantum Number (m_l)

A quantum number used in atomic physics to describe the orientation of an electron's orbital in space. Ranges from -l to l (lowercase L)

Electron Spin Quantum Number (m_s)

A quantum number that describes the intrinsic angular momentum (or spin) of an electron. Has fractional values: -1/2 and 1/2

Orbital diagram

A visual representation of the electron configuration in an atom or molecule

Electron configuration

The distribution of electrons in an atom's orbitals

1

s orbitals have _ orbital(s) per shell

3

p orbitals have _ orbital(s) per shell

5

d orbitals have _ orbital(s) per shell

7

f orbitals have _ orbital(s) per shell

Pauli Exclusion Principle

Principle that states no two electrons can have the same 4 quantum numbers

Hund’s Rule

Rule that states the most stable arrangement of electrons in a subshell is the one with the greatest number of parallel spins

Valence electrons

Outer shell electrons

Isoelectronic atoms/ions

Ions, or atoms and ions, that possess the same number of electrons, and hence the same ground-state electron configuration

s

Transition metals usually form +2 cations because they lose the 2 _ electrons first

1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s…

Order of electron configuration from lowest to highest energy

[Ar] 4s¹3d⁵

Electron configuration of Cr (#24)

[Ar] 4s¹3d¹⁰

Electron configuration of Cu (#29)

Atomic radius

One half the distance between two adjacent nuclei of the same element

left

Atomic radius increases as you go _____ (right/left) on the periodic table

down

Atomic radius increases as you go _____ (up/down) on the periodic table

smaller, bigger

Regarding ionic radius, cations are much _____ (smaller/bigger) than their parent ion, and anions are much _____ (smaller/bigger) than their parent ion

Effective nuclear charge

The nuclear charge felt by an electron when both the actual charge (Z) and the repulsive effect (shielding) of the other electrons are taken into account

Up, right

Effective nuclear charge increases as you go _____ (up/down) on the periodic table and _____ (left/right)

Ionization energy

The minimum energy needed to remove an electron from a gaseous atom in its ground state

Up, right

Ionization energy increases as you go _____ (up/down) on the periodic table and _____ (left/right)

less, drop

Regarding discontinuities in ionization energy, it takes ____ (more/less) energy to remove the lone p electron in Group 3A than to remove a paired s electron in Group 2A, causing a(n) _____ (increase/drop) in ionization energy from 2A to 3A

Easier, lower

Regarding discontinuities in ionization energy, it’s _____ (easier/harder) to remove one of the paired electrons in Group 6A than a half-filled, unpaired electron in Group 5A, leading to a _____ (higher/lower) ionization energy for Group 6A

Electron affinity

The energy change that occurs when an electron is added to a neutral atom to form a negatively charged ion

right, up

Electron affinity increases as you move ____ (right/left) and ____ (up/down) the periodic table

Paramagnetic substance

Substance attracted by a magnet

Diamagnetic substance

Substance repelled by a magnet

paramagnetic, diamagnetic

To determine if an atom is diamagnetic or paramagnetic, examine its electron configuration: if it has unpaired electrons, it is _______; if all electrons are paired, it is _______

Photoelectric effect

Shining light on a clean metal surface causes the ejection of electrons

Node

A region with zero probability of finding an electron