SCI 7 T1 SUMMATIVE

Scientific Model

An abstract, conceptual, graphical, or physical representation of real-world phenomena used to explain, predict, and understand scientific ideas.

Purpose of Scientific Models

To simplify complex phenomena, enable predictions, facilitate hypothesis testing, and support teaching and communication.

Types of Models in Chemistry

Visual representations that help chemists understand molecular structures and predict chemical reactions.

Physics Models

Explain fundamental forces, describe motion, and predict phenomena across microscopic to cosmic scales.

Biological Models

Used to understand life from molecular biology to ecosystems, predicting biological responses and complex interactions.

Earth Science Models

Explain geological processes, weather patterns, and climate change, aiding in disaster preparedness and resource management.

Pure Substances

The simplest forms of matter with a consistent composition, which can be elements or compounds.

Elements

Basic units of matter that cannot be broken down into simpler substances by chemical means.

Compounds

Substances made from two or more elements that are chemically bonded together.

Homogeneous Mixtures

Mixtures where all components are uniformly distributed, such as solutions.

Heterogeneous Mixtures

Mixtures where components are visibly different and not uniformly mixed.

Suspensions

A type of heterogeneous mixture in which particles are suspended in a liquid and may settle over time.

Colloids

A mixture where one substance is dispersed evenly throughout another, like milk.

Gas Particle Movement

Gas particles move freely and rapidly, filling any container completely.

Liquid Particle Arrangement

In liquids, particles are closely packed but can slide past one another, allowing fluidity.

Solid Particle Arrangement

In solids, particles are tightly packed in a fixed position, giving them a definite shape.

Phase Changes

Transformations from one state of matter to another, like melting and vaporization, involving energy changes.

Endothermic Processes

Processes that absorb energy, such as melting ice.

Exothermic Processes

Processes that release energy, such as freezing water.

Effect of Temperature on Particle Movement

Increased temperature causes particles to move faster and spread out, while decreased temperature results in slower movement.

Diffusion Experiment

An experiment showing how particles move and spread evenly in a solution, demonstrating constant particle motion.

Dilution Experiment

Demonstrates the presence of countless tiny particles that maintain a solution's color despite dilution.

Viscosity in Liquids

A measure of a liquid's resistance to flow, influenced by the clustering of particles.

Particle Interaction

The forces of attraction and repulsion between particles that determine the state of matter.

Behavior of Solids Under Heat

Solids vibrate more with increased temperature but maintain their shape due to strong particle attraction.

Behavior of Liquids Under Heat

Liquids can flow and take the shape of their container due to weaker forces of attraction.

Fluid Movement in Liquids

Particles in liquids can slide past each other, leading to a unique flow characteristic.

Behavior of Gases

The rapid and free movement of gas particles allows them to fill available space completely.

Temperature's Role in Cooking

Temperature changes affect the energy of particles, influencing cooking processes like boiling rice.

Energy Dynamics in Phase Changes

Phase changes involve energy exchanges that affect how particles overcome attractive forces.

Refrigeration Technology

Utilizes exothermic processes to cool interiors, crucial for food preservation.