CHEM 110 Lecture Review - Essential Chemistry Concepts

Vocabulary flashcards covering core introductory chemistry definitions including classification of matter, properties, measurement precision/accuracy, historical atomic theory, subatomic particles, isotopes, chemical formulas, and chemical bonding types.

Chemistry

The study of the composition, structure, and properties of matter and how it changes at the molecular and atomic level.

Matter

Anything that occupies space and has mass.

Physical Change

A change in the form or state of matter where the chemical composition remains the same and no new substance is formed.

Chemical Change

A change in composition and properties resulting in the formation of one or more new substances.

Law of Conservation of Matter

A fundamental principle stating that there is no detectable change in the total quantity of matter present during a physical or chemical transformation in a closed system.

Pure Substance

A class of matter that has constant properties and a fixed chemical composition throughout.

Element

A pure substance containing only one kind of atom that cannot be broken down or simplified by chemical means.

Compound

A pure substance composed of two or more different elements combined chemically in fixed whole-number ratios, which can be chemically simplified.

Homogeneous Mixture

A mixture that exhibits a uniform composition and appearance throughout, also referred to as a solution.

Heterogeneous Mixture

A mixture with a composition that varies from point to point, featuring visibly distinguishable components.

Density

An intensive physical property defined as the mass of a substance per unit volume ($\text{density} = \frac{\text{mass}}{\text{volume}}$).

Extensive Property

A property of matter that depends directly on the amount of substance present, such as mass, volume, weight, or energy.

Intensive Property

A property of matter that does not depend on the amount of substance present, such as temperature, density, concentration, or boiling point.

Accuracy

A measure of how close a measured value is to the actual or accepted true value.

Precision

A measure of agreement or closeness among repeated measurement results obtained under the same conditions.

Atomos

A Greek term meaning "indivisible," proposed by Leucippus and Democritus to describe the small, finite particles composing all matter.

Electron

A negatively charged subatomic particle located outside the nucleus, with a fundamental unit charge of $-1$ ($-1.6 \times 10^{-19}\text{ C}$) and a mass of approximately $0.00091 \times 10^{-24}\text{ g}$.

Proton

A positively charged subatomic particle located inside the nucleus, with a fundamental unit charge of $+1$ ($+1.6 \times 10^{-19}\text{ C}$) and a mass of approximately $1.67262 \times 10^{-24}\text{ g}$.

Neutron

An uncharged subatomic particle located inside the nucleus, with a unit charge of $0$ ($0\text{ C}$) and a mass of approximately $1.67493 \times 10^{-24}\text{ g}$.

Atomic Number ($Z$)

The number of protons in the nucleus of an atom, which defines the element's identity.

Mass Number ($A$)

The total number of protons plus neutrons contained within the nucleus of an atom.

Isotopes

Atoms of the same element that contain the same number of protons but different numbers of neutrons, resulting in different mass numbers.

Cation

A positively charged ion formed when a neutral atom (typically a metal) loses one or more electrons.

Anion

A negatively charged ion formed when a neutral atom (typically a nonmetal) gains one or more electrons.

Molecular Formula

A representation using chemical symbols and subscripts to indicate the exact numbers and types of atoms present in a molecule.

Empirical Formula

A chemical formula that shows the types of atoms in a compound expressed as the lowest possible whole-number ratio.

Structural Formula

A representation showing the types and numbers of atoms in a molecule along with lines representing bonds to indicate connectivity.

Ionic Bond

A chemical bond formed by the electrostatic attraction between oppositely charged ions, resulting from the transfer of electrons from a metal atom to a nonmetal atom.

Covalent Bond

A chemical bond formed through the sharing of electron pairs between nonmetal or metalloid atoms.

Polyatomic Ion

A charged species consisting of two or more atoms covalently bonded together that functions as a single ionic unit.