is the scientific study of matter’s composition, structure, properties, behavior, and the changes it undergoes during reactions, including the nature of chemical bonds.

Context: Definition and scope of chemistry

Chemistry is sometimes called the science because it links physics and biology and underpins many basic and applied disciplines.

Context: Chemistry as the central science

The current model of atomic structure is the model, which is used to describe atoms and their behavior.

Context: Modern atomic structure model

A is a symbolic representation of a chemical transformation that typically shows equal numbers of atoms on both sides for chemical reactions.

Context: Chemical equation

A is a transformation of some substances into one or more different substances.

Context: Chemical reaction

Rearrangement of electrons in chemical bonds causes which leads to the formation of one or more different substances.

Context: Cause→effect: electron rearrangement to chemical reaction

Matter is anything with rest mass and volume made of .

Context: Matter and particles

A phase is a set of states with similar structural properties over a range of conditions like temperature and pressure.

Context: Phases and phase transitions: definition of phase

Energy input or removal during a phase transition causes the system’s to rearrange instead of changing only bulk conditions.

Context: Cause→effect: phase transition energy to structural rearrangement

A(n) is a pure substance composed of more than one element whose properties differ from those of its constituent elements.

Context: Compound

An atom has a nucleus (protons and neutrons) surrounded by an .

Context: Atom

The number of protons in an element’s nuclei is the (Z), which defines the element.

Context: Atomic number (Z)

Atoms of the same element that have different mass numbers are called .

Context: Isotopes

A is an interaction that holds atoms together, arising from charge distributions and electron availability.

Context: Chemical bond

Ionic bonding involves electron transfer between atoms, causing one atom to form a(n) .

Context: Ionic bond: electron transfer to form ions