Topic P3 & P4: Particle Model of Matter and Internal Energy Flashcards

Vocabulary-style flashcards covering the particle model of matter, density calculations, internal energy, and specific latent heat based on the provided lecture notes.

Particle model of matter

A model that describes everything as being made up of lots of tiny particles, which can be thought of as tiny balls.

Solid (Arrangement and Energy)

Strong forces hold particles close together in a fixed, regular arrangement; they have not much energy and only vibrate around fixed points.

Liquid (Arrangement and Energy)

Weaker forces hold particles close together in irregular arrangements; they can move past each other in random directions at low speeds.

Gas (Arrangement and Energy)

Almost no forces of attraction between particles mean they are free to move in random directions at a range of high speeds; they have more energy than solids or liquids.

Gas Pressure

The force exerted by gas particles on a unit area of a container's walls as they collide with surfaces.

Outward gas pressure direction

In a sealed container, the net force exerted by particles colliding with the container walls is at right angles to the wall.

Density ($\rho$)

The mass of a substance per unit volume, calculated using the formula $\rho = \frac{m}{V}$. It is usually measured in $\text{kg/m}^3$ or $\text{g/cm}^3$.

Rho ($\rho$)

The Greek letter used as the symbol for density.

Eureka can

A piece of equipment used to find the volume of an irregular solid by measuring the volume of water displaced by the object.

Internal Energy

The total energy that the particles (atoms and molecules) in a system have in their kinetic and potential energy stores.

Kinetic energy stores (within a system)

Energy stored by particles due to their movement or vibration.

Potential energy stores (within a system)

Energy stored by particles due to their positions.

Sublimating

A change of state where a substance turns directly from a solid into a gas.

Conservation of Mass

The principle that mass is not lost during a physical change of state because the number of particles remains the same.

Specific Latent Heat (SLH)

The amount of energy needed to change $1\,\text{kg}$ of a substance from one state to another without changing its temperature.

Specific Latent Heat of Fusion

The specific latent heat for changing between a solid and a liquid (melting or freezing).

Specific Latent Heat of Vaporisation

The specific latent heat for changing between a liquid and a gas (evaporating, boiling, or condensing).

Change of state formula

The formula used to calculate energy needed or released during a state change: $\text{Energy (J)} = \text{Mass (kg)} \times \text{Specific Latent Heat (J/kg)}$.