Chemistry
Particulate model, states, and separation
A source-reviewed Stemosphere lesson shell covering matter as particles, phase changes, mixtures, purity, and separation decisions.
Lesson progress
Describe solids, liquids, and gases using particle arrangement and motion.Connect temperature to average particle kinetic energy.Choose separation techniques based on mixture properties.
Curriculum-source status
This lesson is derived from curriculum-team source notes. Figure references are not public assets until redrawn and approved.
The particulate model explains matter in terms of small particles, their spacing, and their motion. It gives students a common language for comparing solids, liquids, gases, heating curves, cooling curves, and changes of state.
Definition
Temperature
A measure of the average kinetic energy of particles in a sample.
Celsius to Kelvin
K = ^\circ C + 273.15Key idea
During melting or boiling, added energy changes particle arrangement rather than raising temperature, so a heating curve has a plateau.
- Filtration separates an insoluble solid from a liquid.
- Crystallization recovers a soluble solid from solution.
- Distillation separates substances using boiling-point differences.
- Chromatography separates dissolved components by movement through a stationary phase.
Figure needs redraw
Reference figure to redraw: states of matter and heating/cooling curves.
Reference asset tracked internally.