Chemistry Exam Study Guide

A chemical reaction where energy is absorbed from the surroundings, causing the temperature to decrease.

A chemical reaction where energy is released into the surroundings, causing the temperature to increase.

Substances that cannot be broken down into simpler substances by ordinary chemical means.

Changes in matter that only alter its physical appearance, such as shape or state of matter, but do not change its chemical composition.

Changes in matter that result in the formation of new substances with different chemical compositions.

All atoms of the same element have the same number of protons, which defines their atomic number.

Atoms of the same element that have different numbers of neutrons, resulting in different mass numbers.

The arrangement of electrons in an atom's energy levels and sublevels, indicating the electron's energy and location.

The weighted average of the masses of an element's isotopes, considering their relative abundance.

States that each orbital within a subshell is singly occupied with one electron before any orbital is doubly occupied.

A region around the nucleus of an atom that can hold a maximum of two electrons with opposite spins.

The dense, positively charged center of an atom containing protons and neutrons.

Elements belonging to the same vertical column of the periodic table, sharing similar chemical properties and the same number of valence electrons.

Elements in the same period (horizontal row) of the periodic table have increasing electronegativity from left to right.

Elements in Group 15 (Nitrogen group) transition from nonmetallic properties to metallic properties as you move down the group.

The number of electrons in the outermost energy level of an atom. These electrons participate in chemical bonding.

A representation showing the phases of a substance under different conditions of temperature and pressure, illustrating transitions between solid, liquid, and gas states.

The point on a phase diagram where all three phases of a substance coexist.

The point on a phase diagram beyond which a gas cannot be liquefied by increasing pressure, regardless of temperature. Above it, gas and liquid are indistinguishable.

A change in state from a solid directly to a gas.

The process by which gas molecules escape from the surface of a liquid.

A strong type of intermolecular force occurring between molecules with H bonded to N, O, or F atoms. These create strong attractive forces between the molecules.

The attractive forces between molecules, including hydrogen bonding, dipole-dipole interactions, and London dispersion forces.

Forces that hold atoms together within a molecule.

A chemical bond formed between a metal and a nonmetal, where the metal atom loses electrons and becomes a positively charged ion.

A measure of an atom's ability to attract electrons towards itself in a chemical bond.

The shape of a molecule determined by the repulsion between electron pairs in the outer shell of the central atom.

A substance composed of ions held together by electrostatic attraction.

The sharing of electrons between two atoms, resulting in a stable covalent bond.

The tendency of atoms to gain or lose electrons to achieve a stable electron configuration, usually with eight valence electrons.

The chemical composition of a compound can be represented by a chemical formula which shows the types and numbers of atoms present in the compound.

A binary molecular compound is a compound formed by the sharing of electrons between two elements.

The stock system utilizes Roman numerals in parentheses to indicate the charge of a transition metal ion.

The total oxidation numbers of all elements in a neutral compound must add up to zero.

Polyatomic ions containing chlorine and oxygen, like chlorate and chlorite, differ in the number of oxygen atoms they contain.

Polyatomic ions are groups of two or more atoms that carry an overall charge.

The oxidation number of an element in a compound indicates the number of electrons it has gained or lost to form a bond.

In naming compounds, the ending "ide" is often used when the nonmetal is the second element listed, such as oxide (O^-2).