U2S6 Electrons and the Periodic Table - Vocabulary Flashcards

Vocabulary flashcards covering key terms related to electron configurations and the periodic table.

electron configuration

The distribution of electrons in an atom's orbitals; examples include H: 1s1 and He: 1s2; determined by the order of increasing orbital energy across the periodic table.

noble-gas notation

A shorthand electron configuration that replaces inner-shell electrons with the symbol of a noble gas, e.g., [Ne]3s23p3 for phosphorus.

core electrons

Electrons found in the inner shells or lowest energy levels that are not involved in bonding and are generally nonreactive.

valence electrons

Electrons in the outermost shell or highest energy level that determine an atom's reactivity; the last electrons added during building up the configuration.

s-block elements

Elements in Groups 1 and 2; final electron fills an s orbital; valence electrons reside in s orbitals.

p-block elements

Elements in Groups 13–18; final electron fills a p orbital; valence electrons are located in s and p orbitals.

d-block elements

Transition elements in Groups 3–12; final electron fills a d orbital; valence electrons include d electrons.

f-block elements

Inner transition elements; valence electrons reside in s and f orbitals; final electron fills an f orbital.

noble gases

Elements with full valence shells; generally stable and nonreactive.

period

A row of the periodic table; electrons fill orbitals across a period from left to right.

group

A column of the periodic table; the group number often relates to the number of valence electrons.

orbitals

Regions in atoms where electrons are likely to be found (s, p, d, f) and where electrons occupy during configuration.

pathway of filling orbitals

The sequence in which electrons fill orbitals, determined by increasing orbital energy, typically moving left to right across the periodic table.

transition elements

Another term for d-block elements; elements in Groups 3–12 with valence electrons in d orbitals.

inner transition elements

Another term for f-block elements; elements whose valence electrons are in f orbitals.