Periodic Table and Atomic Structure

These flashcards cover key vocabulary and concepts related to the periodic table, atomic structure, and properties of elements as presented in the lecture notes.

Periodic Table

A table that shows all elements along with their chemical symbols, arranged by atomic number.

Chemical Symbol

One or two letter abbreviations for the names of the elements; the first letter is always capitalized and the second letter is lowercase.

Atomic Number

Number of protons in an atom, which determines the identity of an element.

Alkali Metals

Group 1 elements that are soft, shiny, good conductors of heat and electricity, and have low melting points.

Alkaline Earth Metals

Group 2 elements that are harder and denser than alkali metals and are less reactive.

Halogens

Group 17 elements that are non-metals, highly reactive, and exist as diatomic molecules.

Noble Gases

Group 18 elements that are monatomic at room temperature and are mostly inert.

Nonmetals

Elements that are dull, poor conductors of heat and electricity, and can exist in any state.

Metalloids

Elements that exhibit properties intermediate between metals and nonmetals, such as silicon.

Protons

Positively charged particles located in the nucleus of an atom.

Neutrons

Neutral particles located in the nucleus, with a mass of approximately 1 amu.

Electrons

Negatively charged particles located outside the nucleus, with negligible mass.

Mass Number

The sum of protons and neutrons in an atom.

Isotope

Atoms of the same element with the same number of protons but different mass numbers due to different numbers of neutrons.

Photon

A packet of light energy, which can be considered a particle.

Electron Configuration

The arrangement of electrons in an atom, typically represented by exponents.

Hund's Rule

Electrons will not pair up in an orbital until they have to.

Bohr Model

A model of the atom where electrons are located in fixed orbits around the nucleus.

Valence Electrons

Electrons in the outermost energy level of an atom that can be involved in chemical bonds.

Periodic Trends

Patterns in the properties of elements that can be predicted based on their position in the periodic table.

Ionization Energy

The minimum energy required to remove an electron from the ground state of a gaseous atom or ion.

Metallic Character

The ability of an element to lose electrons easily; it increases down a group and decreases across a period.