Electronic Structure and Periodic Properties of Elements

Question 1

Electromagnetic Radiation

Answer 1

Energy transmitted by waves that have an electric-field component and a magnetic-field component

Question 2

Wave

Answer 2

Oscillation of a property over time or space; can transport energy from one point to another

Question 3

Wavelength

Answer 3

Distance between two consecutive peaks or troughs in a wave

Question 4

Frequency

Answer 4

Number of wave cycles (peaks or troughs) that pass a specified point in space per unit time

Question 5

Amplitude

Answer 5

Extent of the displacement caused by a wave

Question 6

Hertz (Hz)

Answer 6

The unit of frequency, which is the number of cycles per second, s^-1

Question 7

Electromagnetic Spectrum

Answer 7

Range of energies that electromagnetic radiation can comprise, included radio, microwaves, infrared, visible, ultraviolet, X-rays, and gamma rays

Question 8

Interference Patterns

Answer 8

Pattern typically consisting of alternativ bright and dark fringes; it results from constructive and destructive interferences of waves

Question 9

Standing Waves (Stationary Waves)

Answer 9

Localized wave phenomenon characterized by discrete wavelengths determined by the boundary conditions used to generate the waves; standing waves are inherently quantized

Question 10

Quantization

Answer 10

Limitation of some property to specific discrete values, not continuous

Question 11

Nodes

Answer 11

Any point of a standing wave with zero amplitude

Question 12

Continuous Spectrum

Answer 12

Electromagnetic radiation given off in an unbroken series of wavelengths (e.g., white light from the sun)

Question 13

Blackbody

Answer 13

Idealized perfect absorber of all incident electromagnetic radiation; such bodies emit electromagnetic radiation in characteristic continuous spectra called blackbody radiation

Question 14

Photons

Answer 14

Smallest possible packet of electromagnetic radiation, a particle of light

Question 15

Wave-Particle Duality

Answer 15

Observation that elementary particles can exhibit both wave-like and particle-like properties

Question 16

Line Spectrum

Answer 16

Electromagnetic radiation emitted at discrete wavelengths by a specific atom (or atoms) in an excited state

Question 17

Bohr’s Model of the Hydrogen Atom

Answer 17

Structural model in which an electron moves around the nucleus only in circular orbits, each with a specific allowed radius

Question 18

Ground State

Answer 18

State in which the electrons in an atom, ion, or molecule have the lowest energy possible

Question 19

Excited State

Answer 19

State having an energy greater than the ground-state energy

Question 20

Quantum Numbers

Answer 20

Number having only specific allowed values and used to characterize the arrangement of electrons in an atom

Question 21

Heisenberg Uncertainty Principle

Answer 21

Rule stating that it is impossible to exactly determine both certain conjugate dynamical properties such as the momentum and the position of a particle at the same time. The uncertainty principle is a consequence of quantum particles exhibiting wave-particle duality

Question 22

Wavefunctions

Answer 22

Mathematical description of an atomic orbital that describes the shape of the orbital; it can be used to calculate the probability of finding the electron at any given location in the orbital, as well as dynamical variables such as the energy and the angular momentum

Question 23

Quantum Mechanics

Answer 23

Field of study that includes quantization of energy, wave-particle duality, and the Heisenberg uncertainty principle to describe matter

Question 24

Principal Quantum Number (n)

Answer 24

Quantum number specifying the shell an electron occupies in an atom

Question 25

Shells

Answer 25

Atomic orbitals with the same principal quantum number, n

Question 26

Atomic Orbital

Answer 26

Mathematical function that describes the behavior of an electron in an atom (also called the wavefunction)

Question 27

Secondary (Angular Momentum) Quantum Number (l)

Answer 27

Quantum number distinguishing the different shapes of orbitals; it is also a measure of the orbital angular momentum

Question 28

Subshell

Answer 28

Atomic orbitals with the same values of n and l

Question 29

S Orbitals

Answer 29

Spherical region of space with high electron density, describes orbitals with l=0

Question 30

P Orbitals

Answer 30

Dumbbell-shaped region of space with high electron density, describes orbitals with l=1

Question 31

D Orbitals

Answer 31

Region of space with high electron density that is either four lobed or contains a dumbbell and torus shape; describes orbitals with l=2

Question 32

F Orbitals

Answer 32

Multilobed region of space with high electron density, describes orbitals with l=3

Question 33

Magnetic Quantum Number

Answer 33

Quantum number signifying the orientation of an atomic orbital around the nucleus

Question 34

Degenerate Orbitals

Answer 34

Orbitals that have the same energy

Question 35

Spin Quantum Number (m sub s)

Answer 35

Number specifying the electron spin direction, either +1/2 or -1/2

Question 36

Pauli Exclusion Principle

Answer 36

Specifies that no two electrons in an atom can have the same value for all four quantum numbers

Question 37

Electron Configuration

Answer 37

Listing that identifies the electron occupancy of an atom’s shells and subshells

Question 38

Aufbau Principle

Answer 38

Procedure in which the electron configuration of the elements is determined by “building” them in order of atomic numbers, adding one proton to the nucleus and one electron to the proper subshell at a time

Question 39

Orbital Diagram

Answer 39

Pictorial representation of the electron configuration showing each orbital as a box and each electron as an arrow

Question 40

Hund’s Rule

Answer 40

Every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in a singly occupied orbitals have the same spin

Question 41

Valence Electrons

Answer 41

Electrons in the high energy outer shell(s) of an atom

Question 42

Core Electrons

Answer 42

Electron in an atom that occupies the orbitals of the inner shells

Question 43

Valence Shell

Answer 43

High energy outer shell(s) of an atom

Question 44

Covalent Radius

Answer 44

One-half the distance between the nuclei of two identical atoms when they are joined by a covalent bond

Question 45

Effective Nuclear Charge (Z sub eff)

Answer 45

Charge that leads to the Coulomb force exerted by the nucleus on an electron, calculated as the nuclear charge minus shielding

Question 46

Isoelectronic

Answer 46

Group of ions or atoms that have identical electron configurations

Question 47

Ionization Energy

Answer 47

Energy required to remove an electron from a gaseous atom or ion

Question 48

Electron Affinity

Answer 48

Energy change associated with addition of an electron to a gaseous atom or ion