Matter, Materials, Processing, and Water Purification

Vocabulary practice flashcards covering particle theory, states of matter, phase transitions, solutions, dissolving factors, water pollution, wetlands, and water purification methods.

Matter

Everything around us that makes up all the materials on Earth; it consists of tiny particles that are always moving or vibrating and have spaces between them.

Atom

A tiny particle of matter, far too small to be seen with a normal microscope, composed of a dense central nucleus and electrons flying around it.

Nucleus (atomic)

The extremely small central region of an atom consisting of protons and neutrons.

Solid

A state of matter where particles are tightly packed in a regular pattern with small spaces between them, vibrating only in fixed positions to give a fixed shape.

Liquid

A state of matter where particles are closely packed but without a fixed pattern, able to move past one another freely so the substance can flow and take the shape of its container.

Gas

A state of matter where particles are very far apart with large spaces between them, moving freely and rapidly in all directions with no fixed shape.

Melting

A reversible phase transition from solid to liquid that occurs when heat energy is added to a single substance.

Sublimation

The phase transition in which a substance changes directly from a solid into a gas without passing through the liquid state.

Deposition

The phase transition in which a substance changes directly from a gas into a solid without passing through the liquid state.

Mixture

A combination consisting of two or more different substances mixed together physically.

Solution

A special uniform mixture formed when solute particles break down into very fine particles that disperse into the spaces between liquid solvent particles.

Solute

The substance (such as salt or sugar) that dissolves into a liquid solvent to create a solution.

Solvent

The liquid (such as water) in which a solute dissolves to form a solution.

Solubility

The ability of one substance to dissolve into another substance.

Insoluble

Describes a substance (such as sand or plastic) that does not dissolve when placed in a liquid.

Crystallisation

A separation process where the liquid solvent is evaporated from a solution, leaving solid crystals of the solute behind.

Filtering

A separation method in which a liquid mixture is poured through porous material (such as filter paper or cloth) to trap solid particles while allowing liquid to pass through.

Volume

The amount of physical space an object or substance occupies, commonly measured in milliliters or liters.

Mass

A measure of the quantity of matter contained within a substance, measured in grams or kilograms.

Tare

A function or button on a digital balance used to reset the reading to zero, excluding the mass of the container or bowl.

Saturated solution

A solution that has dissolved the maximum possible amount of solute at a given temperature, so no more solute can dissolve and excess settles at the bottom.

Rate of dissolving

The speed at which a solute dissolves into a solvent, determined by temperature, stirring or shaking, and solute grain size.

Water pollution

The contamination of water sources by human actions that introduce insoluble objects, dissolved chemicals, or biological germs, rendering it unsafe.

Faeces

The proper term for solid bodily toilet waste produced by humans and animals.

Cholera

A severe waterborne diarrhoeal infection caused by germs found in water contaminated with human faeces, responsible for over $100\,000$ deaths annually worldwide.

Wetland

An area of land (such as a marsh, swamp, or vlei) saturated or covered with shallow water for most of the year, acting as a natural sponge and water filter.

Biodiversity

The variety of all different kinds of plants, animals, and other living organisms found within a particular ecosystem.

Water quality

A description of how clean, pure, and safe water is for consumption and use by living organisms.

Water purification

The process of removing harmful substances, solids, and disease-causing germs from contaminated water to make it safe to drink.

Sieving

A mechanical cleaning process where water is passed through a mesh screen to separate larger solid materials like rocks and dirt.

Settling

A water treatment step where dirty water is kept undisturbed so heavier suspended solid particles sink to the bottom under gravity.

Decanting

The technique of slowly pouring off the clear upper liquid from one container to another without disturbing the settled solid layer at the bottom.

Chlorine

The most common chemical disinfectant added in precise amounts to water to kill harmful germs, bacteria, and parasites.

Sludge

The muddy solid residue that settles at the bottom of sedimentation tanks in municipal water treatment plants, which is suctioned out during treatment.

Chloramine

A chemical disinfectant formed from chlorine and ammonia, added to municipal water at regular intervals to maintain long-lasting protection against germs.