AP Chemistry Unit 1: Atomic Structure and Properties Flashcards

Vocabulary flashcards covering key concepts from Unit 1 of AP Chemistry, including mole concepts, mass spectrometry, percent composition, photoelectron spectroscopy, Coulomb's law, and periodic trends.

Constituent Particles

The small pieces or building blocks that make up a larger object or substance.

Mole

A unit measurement representing $6.02 \times 10^{23}$ constituent particles of a substance.

Molar Mass

The mass in grams of one mole of a substance ($g\,mol^{-1}$), which is numerically equal to its formula mass in atomic mass units ($u$).

Conversion Factor

A ratio or fraction representing the mathematical relationship between the same quantity in two different units.

Mass Spectrometry

An experimental technique used to identify the isotopes of an element and measure their relative abundances in nature to calculate average atomic mass.

Empirical Formula

The lowest whole-number ratio of atoms of each element present in a compound.

Molecular Formula

The formula that specifies the actual number of atoms of each element present in a compound.

Combustion Analysis

A laboratory method of burning a sample in $O_2(g)$ and analyzing the reaction products to determine the relative amounts of carbon and hydrogen.

Hydrate Analysis

An analytical technique where a hydrated ionic solid is heated to calculate the mass change and determine the mole ratio of water to anhydrous solid.

Mixture

A combination of two or more pure substances that are not chemically combined and can be separated using physical methods.

Solution

A homogeneous mixture formed when a solute is dissolved in a solvent.

Coulomb's Law

A formula stating that the electrostatic force between two charged particles is proportional to the product of their charges and inversely proportional to the square of the distance between them ($F \propto \frac{q_1 q_2}{r^2}$).

Ionization Energy

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

Aufbau Principle

The rule stating that electrons fill lower-energy atomic subshells completely before occupying higher-energy subshells.

Photoelectron Spectroscopy (PES)

An experimental technique that uses high-energy radiation to remove electrons from atoms, measuring binding energy (peak position) and electron count (peak height).

Core Electrons

Electrons located in inner energy shells that experience a higher attraction to the nucleus and require more energy to remove.

Valence Electrons

Electrons located in the outermost energy shell of an atom that participate in chemical bonding.

Atomic Radius

A measurement of atomic size that increases down a group due to added electron shells and decreases across a period due to increased nuclear charge.

Electronegativity

The relative ability of an atom within a chemical bond to attract shared electrons to itself.

Electron Affinity

The energy change that occurs when an electron is added to a neutral gaseous atom to form a negative ion.