Chapter 2: The Structure of the Atom and the Periodic Table

Practice flashcards based on key concepts from Chapter 2 covering atomic structure, periodic table trends, and electron configurations.

What is the atomic theory credited to Ernest Rutherford?

The nuclear model for atomic structure.

What does the atomic number (Z) represent?

The number of protons in an atom.

What is an isotope?

Atoms with the same number of protons but different numbers of neutrons.

What is the definition of a cation?

A positively charged atom where the number of protons exceeds the number of electrons.

What principle states that electrons fill the lowest energy orbitals first?

Aufbau principle.

What is the formula for calculating atomic mass?

Atomic mass = ∑ (isotopic mass) * (natural abundance/100).

What does the principal quantum number (n) describe?

The size of the orbital and identifies the row of the periodic table.

What trend is observed for atomic radii across a period?

Atomic radii decrease across a period.

What is the trend of ionization energy down a group?

Ionization energy decreases down a group.

How does metallic character change across a period?

Metallic character decreases across a period.