The Particle Nature of Matter

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Matter Noun

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[mat-er]

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Matter

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Anything that has mass and occupies space, composed of tiny particles such as atoms and molecules.

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Example: This image shows that matter is made of particles. It compares how these particles are arranged in solids (tightly packed), liquids (close but random), and gases (far apart).

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Atom Noun

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[at-uhm]

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Atom

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The fundamental building block of matter and the smallest representative unit of a chemical element.

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Example: This diagram shows an atom's structure: a central nucleus containing protons and neutrons, with electrons orbiting the nucleus in distinct energy shells.

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Element Noun

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[el-uh-muhnt]

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Element

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The simplest form of matter that possesses a unique and characteristic set of physical and chemical properties.

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Example: This diagram shows an atom, the basic building block of an element, made of protons, neutrons, and electrons in their specific locations.

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Chemical Symbol Noun

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[kem-i-kuhl sim-buhl]

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Chemical Symbol

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A one or two-letter abbreviation used to represent a specific chemical element on the periodic table.

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Example: This image shows that the letters 'H' and 'O' are the chemical symbols for the elements Hydrogen and Oxygen, which are the building blocks of matter.

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Molecule Noun

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[mol-i-kyool]

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Molecule

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A neutral particle formed when two or more atoms are chemically combined and held together by chemical bonds.

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Example: This image shows a single water molecule, made of two hydrogen (H) atoms and one oxygen (O) atom chemically bonded together.

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Chemical Bond Noun

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[kem-i-kuhl bond]

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Chemical Bond

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A strong force of attraction that holds two or more atoms together within a molecule or compound.

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Example: This image shows a water molecule where one oxygen atom (O) and two hydrogen atoms (H) are held together by connections, which represent chemical bonds.

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Chemical Formula Noun

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[kem-i-kuhl fawr-myoo-luh]

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Chemical Formula

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A representation showing the types and numbers of atoms present in one molecule of a substance.

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Example: This image shows a glucose molecule and its chemical formula, C₆H₁₂O₆. The formula is a shorthand telling us it contains 6 carbon, 12 hydrogen, and 6 oxygen atoms.

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Density Noun

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[den-si-tee]

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Density

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A physical property of matter defined as the amount of mass contained within a given volume.

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Example: This image shows two cubes of the same volume on a balance beam. The cube with more particles packed inside has more mass, making it denser.

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Energy Noun

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[en-er-jee]

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Energy

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The capacity to perform work, move matter, cause change, or produce heat in a system.

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Example: This diagram shows electric energy, where tiny particles called electrons flow from a battery through a wire (conductor) to power a light bulb.

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Kinetic Energy Noun

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[ki-net-ik en-er-jee]

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Kinetic Energy

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The form of energy that matter possesses due to the constant motion of its constituent particles.

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Example: This diagram shows that as matter changes from solid to liquid to gas, its particles move faster, demonstrating an increase in their kinetic energy.