General Chemistry - Chapter 2 Flashcards

Vocabulary practice flashcards generated from lecture notes covering atomic structure history, subatomic discovery experiments, isotope notation, periodic table groups, ionic and covalent naming, and organic functional groups.

Atomos

The Greek term meaning indivisible, proposed around 500 BC by Leucippus and Democritus to describe the smallest material unit of an element.

Law of Conservation of Mass

Formulated by Antoine Lavoisier, it states that matter cannot be created or destroyed in a chemical reaction (except in nuclear reactions), only changing form and composition.

Law of Definite Proportions

Also known as the Law of Constant Composition, formulated by Joseph Proust, it states that a pure compound always contains the same elements in the same mass proportions.

Law of Multiple Proportions

Formulated by John Dalton, it states that when two elements combine in more than one proportion to form two or more compounds, the weights of one element combining with a given weight of the other are in ratios of small whole numbers.

Dalton's Atomic Theory

A theory proposed in 1803 by John Dalton stating that elements are composed of indivisible atoms, atoms of a given element are identical, and compounds form when atoms combine in fixed, whole-number ratios.

Brownian Motion

Discovered by Robert Brown in 1827 through observing pollen grains moving in complex paths in water, providing early physical evidence for the existence of atoms.

Cathode Ray Tube Experiment

Conducted by J. J. Thomson in 1897 using electrical and magnetic fields to discover the electron and determine its mass-to-charge ratio.

Millikan's Oil Drop Experiment

An experiment performed by R. A. Millikan in 1909 measuring the fall rate of ionized oil droplets in an electric field to calculate the fundamental electric charge of an electron ($1.6 \times 10^{-19}\,\text{C}$).

Alpha Particles (\alpha particles)

Positively charged radioactive decay particles described by Ernest Rutherford that undergo small deflections in an electric field due to their high mass.

Beta Particles (\beta particles)

Negatively charged radioactive decay particles described by Ernest Rutherford that undergo large deflections in an electric field due to their low mass.

Gamma Rays (\gamma rays)

High-energy radiation emitted during radioactive decay that carries no electrical charge and passes through electric fields without deflection.

Plum Pudding Model

An atomic model proposed by J. J. Thomson in 1904 depicting electrons embedded within a uniform sphere of positive charge.

Rutherford's Gold Foil Experiment

An experiment in 1911 in which alpha particles were deflected by thin gold foil, demonstrating that the atom has a small, dense, positively charged nucleus.

Atomic Mass Unit (amu)

A unit of mass defined relative to the \text{^{12}C} isotope standard, equal to approximately $1.66054 \times 10^{-24}\,\text{g}$.

Atomic Number (Z)

The number of protons contained in the nucleus of an atom, uniquely identifying a chemical element.

Mass Number (A)

The total combined count of protons and neutrons in an atom's nucleus.

Isotopes

Atoms of the same element that possess the same atomic number (protons) but different mass numbers due to varying numbers of neutrons.

Alkali Metals

Group 1 main group elements on the periodic table that readily lose an electron to form cations with a $+1$ charge.

Alkaline Earth Metals

Group 2 main group elements on the periodic table that form cations with a $+2$ charge.

Halogens

Group 17 nonmetal elements on the periodic table that readily gain an electron to form anions with a $-1$ charge.

Chalcogenides

Group 16 elements on the periodic table that commonly form anions with a $-2$ charge.

Cation

A positively charged ion produced when a neutral atom loses electrons, resulting in more protons than electrons.

Anion

A negatively charged ion produced when a neutral atom gains electrons, resulting in more electrons than protons.

Empirical Formula

A chemical formula expressing the simplest relative whole-number ratio of atoms of each element in a compound.

Molecular Formula

A chemical formula that states the exact actual number of atoms of each element in a molecule.

Polyatomic Ion

A group of covalently bonded atoms that carries an overall net electrical charge.

Oxyanions

Polyatomic anions containing oxygen bonded to another element, named using prefixes and suffixes based on the relative count of oxygen atoms.

Hydrate

An inorganic salt compound that has water molecules chemically bound within its crystalline matrix.

Deliquescent

A property of a chemical substance (such as $\text{NaOH}$) that absorbs enough moisture from the surrounding air to dissolve itself into an aqueous solution.

Hydrocarbon

An organic chemical compound comprised entirely of carbon and hydrogen atoms.

Alkanes

Hydrocarbons containing only single carbon-carbon bonds ($\text{C-C}$).

Alkenes

Hydrocarbons containing at least one double carbon-carbon bond ($\text{C=C}$).

Alkynes

Hydrocarbons containing at least one triple carbon-carbon bond ($\text{C}\equiv\text{C}$).

Alcohols

A family of organic compounds characterized by a hydroxyl functional group ($\text{R-OH}$) and ending with the suffix -ol.

Carboxylic Acids

A family of organic compounds containing a carboxyl group ($\text{R-C(=O)OH}$) and named with the suffix acid.