General Chemistry: Matter, Measurements, Atomic Structure, and Reactions

Vocabulary flashcards covering Matter, Measurements, Atomic Structure, Periodic Table, Nomenclature, Chemical Reactions, and Reaction Stoichiometry.

Chemistry

The study of the characteristics, composition, and transformations of matter.

Matter

Anything that has mass and occupies space.

Particulate Matter

Matter that is too small to be seen even with a microscope, including atoms, molecules, and ions.

Crystalline Solids

Solids characterized by a well-organized, repeating pattern of constituent particles.

Amorphous Solids

Solids, such as glass, that lack a regular repeating particle pattern.

Element

The simplest type of substance with unique properties, made of only one type of atom, which cannot be broken down chemically or physically into simpler substances.

Compound

A pure substance formed when two or more different elements chemically bond together in a fixed ratio.

Homogeneous Mixture

A mixture that is uniform throughout and consists of a single phase, also commonly referred to as a solution.

Heterogeneous Mixture

A mixture that is not uniform throughout, containing visually distinguishable phases or components.

Physical Properties

Characteristics of matter that can be observed or measured without changing the chemical composition of the substance.

Chemical Properties

Characteristics describing how a substance behaves during a chemical reaction when its composition changes or resists change.

Intensive Properties

Properties of matter that do not depend on the quantity of sample present, such as density, melting point, and boiling point.

Extensive Properties

Properties of matter that depend directly on the quantity of sample present, such as mass, length, and volume.

Physical Change

A process that results in no change in the chemical composition of matter, such as changes of state or dissolution.

Chemical Change

A process in which one or more substances undergo composition changes to form new chemical substances.

Filtration

A physical separation technique for mixtures that utilizes differences in solubility to trap insoluble solids on a filter.

Distillation

A physical separation technique involving the boiling of a liquid mixture to produce vapor and recondensing it to isolate pure liquid components.

Precision

Refers to how close multiple experimental measurements of the same quantity are to one another.

Accuracy

Refers to how close a measured experimental value is to the known or accepted true value.

Significant Figures

All the digits in a measured quantity that are known with certainty plus the first estimated digit.

Dimensional Analysis

A problem-solving methodology that relies on conversion factor fractions and unit cancellation to convert between measurements.

Law of Conservation of Mass

A law stating that mass cannot be created or destroyed in a chemical reaction, ensuring total product mass equals total reactant mass.

Law of Definite Proportions

A law stating that all samples of a pure compound contain the same elements in the exact same proportion by mass.

Law of Multiple Proportions

A law stating that when two elements form several compounds, holding the mass of one element fixed yields masses of the second element in small whole-number ratios.

Cathode Ray Tube (CRT)

An evacuated glass tube containing electrodes that produces a stream of negatively charged particles traveling from cathode to anode when high voltage is applied.

Electron

A subatomic particle discovered by J.J. Thomson with a charge-to-mass ratio of $-1.76 \times 10^8\,\text{C/g}$, a relative charge of $-1$, and a mass of $9.110 \times 10^{-28}\,\text{g}$.

Plum Pudding Model

An atomic model proposed by J.J. Thomson depicting the atom as a positive sphere of mass with negative electrons embedded throughout.

Gold Foil Experiment

An experiment conducted by Ernest Rutherford's group bombarding gold leaf with alpha particles, showing that most particles passed through while a few deflected, establishing the nuclear model of the atom.

Atomic Nucleus

The extremely dense central region of an atom containing protons and neutrons, occupying $0.005\%$ of atomic volume while housing $99.97\%$ of atomic mass.

Proton

A positively charged subatomic particle located in the nucleus with a charge of $+1.60 \times 10^{-19}\,\text{C}$, relative charge $+1$, and mass of $1.673 \times 10^{-24}\,\text{g}$ ($1.0073\,\text{amu}$).

Neutron

A uncharged subatomic particle discovered by James Chadwick located in the nucleus with a mass of $1.675 \times 10^{-24}\,\text{g}$ ($1.0087\,\text{amu}$).

Atomic Number ($Z$)

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

Mass Number ($A$)

The total count of protons plus neutrons in the nucleus of an atom.

Isotopes

Atoms of the same element that share the same atomic number ($Z$) but differ in neutron count and mass number ($A$).

Cation

A positively charged ion produced when a neutral atom or group of atoms loses one or more electrons.

Anion

A negatively charged ion produced when a neutral atom or group of atoms gains one or more electrons.

Atomic Mass Unit (amu)

A unit of mass defined as exactly $1/12$ the mass of a single carbon-12 ($^{12}\text{C}$) atom, equal to $1.66054 \times 10^{-24}\,\text{g}$.

Atomic Weight

The weighted average relative atomic mass of all naturally occurring isotopes of an element in atomic mass units.

Ionic Bonding

A chemical bonding force driven by electrostatic attraction between oppositely charged cations and anions, typically involving electron transfer between metals and nonmetals.

Covalent Bonding

A chemical bond formed when nonmetal atoms share pairs of valence electrons to achieve stability.

Formula Unit

The simplest integer ratio representation of cations to anions in an ionic compound crystal lattice.

Polyatomic Ion

A group of covalently bonded atoms carrying a net positive or negative charge that acts as a single chemical unit.

Base

A substance that produces or increases hydroxide ion ($\text{OH}^-$) concentration in water, displaying a pH greater than $7$, bitter taste, and slippery feel.

Acid

A substance that produces or increases proton ($\text{H}^+$) concentration in water, displaying a pH less than $7$, sour taste, and corrosive action.

Combination Reaction

A reaction class in which two or more separate reactants combine to form a single combined product ($A + B \rightarrow C$).

Decomposition Reaction

A reaction class in which a single reactant breaks apart into two or more products ($C \rightarrow A + B$).

Combustion Reaction

A reaction in which an organic carbon-containing compound burns in oxygen gas ($\text{O}_2(g)$) to yield carbon dioxide ($\text{CO}_2(g)$) and water vapor ($\text{H}_2\text{O}(g)$).

Mole (mol)

The standard unit for measuring amount of substance, equal to the number of carbon atoms in $12\,\text{g}$ of carbon-12 ($6.022 \times 10^{23}$ particles).

Avogadro's Number ($N_A$)

The physical constant representing particle count per mole of substance, equal to $6.022 \times 10^{23}\,\text{particles\,mol}^{-1}$.

Molar Mass

The mass in grams corresponding to one mole of a given element or compound, expressed in units of $\text{g\,mol}^{-1}$.

Mass Percent

The mass contribution of a specific element in one mole of compound divided by the compound's total molar mass, expressed as a percentage.

Empirical Formula

The chemical formula representing the lowest whole-number ratio of elements present in a compound.

Molecular Formula

A chemical formula indicating the actual, exact number of each atom type present in a molecule of a covalent compound.

Stoichiometry

The quantitative relationship between amounts of reactants and products in a balanced chemical equation derived from mole ratios.

Theoretical Yield

The calculated maximum mass of product that can form in a reaction based on starting reactant quantities.

Percent Yield

The measure of reaction efficiency calculated as $\text{Percent Yield} = \frac{\text{Actual Yield}}{\text{Theoretical Yield}} \times 100\%$.

Limiting Reactant

The reactant that is completely consumed first during a chemical process, restricting the maximum amount of product formed.