Chemistry Fundamentals

Chemistry is the scientific study of matter, its properties, composition, structure, and the changes it undergoes during chemical reactions.

Matter is anything that has mass and occupies space. It exists in three primary states: solid, liquid, and gas.

The three main states of matter are solid (definite shape and volume), liquid (definite volume but indefinite shape), and gas (neither definite shape nor volume).

An element is a pure substance that cannot be broken down into simpler substances by chemical means and is made of only one type of atom.

A compound is a pure substance composed of two or more different elements chemically bonded in fixed proportions.

A mixture is a combination of two or more substances that are not chemically combined and retain their individual properties. Mixtures can be homogeneous (uniform) or heterogeneous (non-uniform).

An atom is the smallest unit of an element that retains the chemical properties of that element, consisting of a nucleus and electrons.

The three main subatomic particles are protons (positive charge in nucleus), neutrons (no charge in nucleus), and electrons (negative charge orbiting nucleus).

The atomic number is the number of protons in an atom's nucleus, which defines the element and its position in the periodic table.

The mass number is the total number of protons and neutrons in an atom's nucleus.

Isotopes are atoms of the same element with the same atomic number but different mass numbers due to varying numbers of neutrons.

The periodic table is a tabular arrangement of chemical elements organized by increasing atomic number, showing periodic trends in properties.