Light, Electrons, & the Periodic Table - Flashcards

A comprehensive set of QUESTION_AND_ANSWER style flashcards covering light, atomic structure, quantum numbers, electron configurations, and periodic trends from the lecture notes.

What is light classified as in terms of energy and radiation?

Light is a form of energy and a form of electromagnetic radiation.

Through what does electromagnetic radiation move, similar to waves across a pond?

Electromagnetic radiation moves through space like waves.

Name the four characteristics that define a wave.

Wave speed, amplitude (height), wavelength, and frequency (number of crests passing a point per unit time).

What is the speed of light in a vacuum?

3.00 x 10^8 meters per second (c).

How do short wavelengths relate to frequency in electromagnetic waves?

Short wavelength corresponds to high frequency; long wavelength corresponds to low frequency.

What does the equation E = hv describe in light physics?

The energy of a photon equals Planck’s constant times its frequency (E = hv).

What is Planck’s constant value used in these notes?

h = 6.626 x 10^-34 J·s.

What is the relationship between frequency and wavelength in light?

v = c/λ, where c is the speed of light and λ is wavelength.

What happens when light passes through a prism?

Light is separated into a continuous spectrum, and color is determined by wavelength.

How can spectra be used to identify elements?

The spectrum of wavelengths emitted or absorbed is characteristic of each element and can identify it.

What is an orbital in the quantum-mechanical model?

A region in an atom with a high probability of finding an electron for a given energy.

What does a quantum number describe in Schrödinger’s model?

Integer values (n, l, ml) that quantify energy levels and orbitals.

What does the principal quantum number n describe?

The energy level or shell; n = 1, 2, 3, …; lower n means lower energy.

What does the angular momentum quantum number l describe?

The orbital shape; values 0 to n−1; corresponds to subshells (s, p, d, f, g).

Which letters designate subshells for l = 0, 1, 2, 3, 4?

0→s, 1→p, 2→d, 3→f, 4→g.

What does the magnetic quantum number ml specify?

The orientation of the orbital in space; ml ranges from −l to +l.

What is an orbital in simple terms?

A region with a very high probability of finding an electron for a given energy.

Name the three quantum numbers that quantize energy in Schrödinger’s model.

n (principal), l (azimuthal), and ml (magnetic).

What does the Aufbau principle state about electron filling?

Electrons fill from the lowest energy to the highest; subshells of the same energy fill by placing one electron in each orbital before pairing.

What does Hund’s rule require when filling degenerate orbitals?

Maximize the number of unpaired electrons (one in each orbital before pairing).

What does the Pauli exclusion principle state about electrons in an orbital?

An orbital holds at most two electrons, and they must have opposite spins.

What is an electron configuration?

The arrangement of electrons in occupied orbitals in an atom in its ground state (e.g., H: 1s1; He: 1s2).

How is a noble gas core used in electron configurations?

Abbreviated configurations use [NobleGas] to represent core electrons, e.g., Cl: [Ne]3s2 3p5.

What are valence electrons?

Electrons in the outermost energy shell; they largely determine chemical behavior.

How many valence electrons do noble gases typically have, and which exception exists?

Eight valence electrons for all noble gases except Helium, which has two.

What is the general trend of metallic character on the periodic table?

Metals are on the left; metallic character increases down a group and decreases across a period from left to right.

How does atomic size change down a group and across a period?

Atomic size increases down a group and decreases across a period (left to right).

What is ionization energy?

The minimum energy required to remove an electron from a gaseous atom; the process is endothermic.

Which electron is easiest to remove (in terms of ionization energy)?

The valence electron.

How do metals and nonmetals typically achieve stable electron configurations?

Metals lose valence electrons to form cations; nonmetals gain valence electrons to form anions.

What is a typical electron configuration for Neon?

1s2 2s2 2p6.

What is a typical electron configuration for Magnesium?

1s2 2s2 2p6 3s2.

What is the approximate wavelength range of visible light?

Approximately 400 to 700 nm.

What is a continuous spectrum?

A spectrum produced when light is separated into all colors by a prism.

What is the symbol for the speed of light?

c, equal to 3.00 x 10^8 m/s.

What does E = hv imply about photon energy?

Photon energy is proportional to its frequency; higher frequency means higher energy.