Matter in Our Surroundings - Vocabulary Flashcards

Vocabulary flashcards covering key terms from the Matter in Our Surroundings notes.

Matter

Anything that occupies space and has mass; composed of particles; exists in states such as solid, liquid and gas.

Mass

The quantity of matter in an object; SI unit is kilogram (kg).

Volume

The space occupied by matter; SI unit is cubic metre (m^3); common unit is litre (L); 1 L = 1 dm^3, 1000 mL.

Panch Tatva

Ancient Indian concept of five elements—air, earth, fire, sky, and water—that make up all matter.

Particle

A tiny unit of matter; there is space between particles and they possess kinetic energy.

Diffusion

Intermixing of substances due to the random motion of particles; rate increases with temperature.

Solid

State with definite shape and volume; rigid; high inter-particle forces; negligible compressibility.

Liquid

State with definite volume but no fixed shape; takes the shape of its container and flows.

Gas

State with no fixed shape or volume; highly compressible; particles move rapidly and diffuse quickly; pressure from collisions with container walls.

Melting Point

Temperature at which a solid changes to a liquid at atmospheric pressure.

Fusion

Process of melting; solid turning into liquid.

Boiling Point

Temperature at which a liquid boils at atmospheric pressure; boiling is a bulk change from liquid to gas.

Sublimation

Direct change from solid to gas without passing through liquid (e.g., camphor).

Deposition

Direct change from gas to solid without passing through liquid.

Latent Heat of Fusion

Heat energy required to convert 1 kg of solid into liquid at the melting point without a temperature change.

Latent Heat of Vaporisation

Heat energy required to convert 1 kg of liquid into gas at the boiling point without a temperature change.

Density

Mass per unit volume; SI unit is kilogram per cubic metre (kg/m^3).

Evaporation

Change of a liquid to a gas from the surface below the boiling point; rate depends on surface area, temperature, humidity, and wind speed; causes cooling.

Latent Heat

Hidden heat energy absorbed or released during a phase change when temperature remains constant.

Pressure

Force per unit area exerted by gas on the walls of its container; SI unit is pascal (Pa); 1 atm \approx 1.01 \times 10^5 Pa.

Temperature (Kelvin)

SI unit of temperature; 0°C = 273.15 K; conversion between Celsius and Kelvin.

Phase Interconversion

State changes among solid, liquid, and gas caused by changes in temperature or pressure.