The Properties of Matter

Density is a physical property that describes the mass of a substance per unit volume. It is an intensive property, meaning that it does not depend on the amount of matter present.

The SI unit of mass is the kilogram (kg).

Flammability is a chemical property that describes the ability of a substance to burn. It depends on the chemical composition of the substance.

All of the above statements are true. A physical change is a change in the form or appearance of a substance, while a chemical change is a change in the chemical composition of a substance.

Melting of ice is a physical change because it involves the rearrangement of water molecules from a solid to a liquid state. No new substances are produced.

Fermentation of grapes is a chemical change because it involves the conversion of grape juice into ethanol and carbon dioxide. New substances are produced.

A solid is a state of matter in which a substance has a definite shape and volume. The particles in a solid are held together by strong intermolecular forces.

A liquid is a state of matter in which a substance has a definite volume but no definite shape. The particles in a liquid are held together by weaker intermolecular forces than in a solid.

A gas is a state of matter in which a substance has no definite shape or volume. The particles in a gas are very far apart and have very weak intermolecular forces.

Plasma is the fourth state of matter. It is a highly ionized gas in which the electrons are separated from the nuclei. Plasma is found in stars, lightning, and other high-energy environments.

The three main types of particles that make up matter are protons, neutrons, and electrons. Protons and neutrons are found in the nucleus of an atom, while electrons orbit the nucleus.

An atom is the smallest unit of an element that can exist. It consists of a nucleus, which contains protons and neutrons, and electrons, which orbit the nucleus.

A compound is a substance that is made up of two or more different elements. The elements in a compound are chemically combined in a specific ratio.

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

An ion is a substance that has a net electric charge. Ions are formed when atoms lose or gain electrons.