1.1 Flashcards
Pure Substance
A material with a constant composition; it contains only one type of particle and has distinct chemical properties.
Element
A pure substance that consists of only one type of atom and cannot be broken down by chemical means.
Example: Oxygen (O), Carbon (C)
Compound
A pure substance made of two or more different elements chemically bonded in a fixed ratio.
Example: Water (H₂O), Carbon Dioxide (CO₂)
Mixture
A combination of two or more substances that are not chemically bonded and can be separated by physical means.
Heterogeneous Mixture
A mixture in which the composition is not uniform; different components are visibly distinct.
Example: Salad, Sand and Iron Filings
Homogeneous Mixture
A mixture in which the composition is uniform throughout; also known as a solution.
Example: Saltwater, Air
Filtration
A separation technique used to separate an insoluble solid from a liquid.
Example: Sand and water mixture
Distillation
A process used to separate mixtures based on differences in boiling points, often separating a liquid from a solution.
Example: Separating alcohol from water
Paper Chromatography
A technique used to separate substances based on their solubility in a solvent, often used to separate colored pigments.
Solid
Definite shape and volume, particles are closely packed in a fixed arrangement and vibrate in place.
Example: Ice, Iron
Liquid
Definite volume but no fixed shape, takes the shape of its container, particles are close but can slide past each other.
Example: Water, Oil
Gas
No definite shape or volume, expands to fill the container, particles are far apart and move freely.
Example: Oxygen (O₂), Carbon Dioxide (CO₂)
Melting
The change of state from solid to liquid as heat is absorbed, causing particles to gain energy and move more freely.
Freezing
The change of state from liquid to solid as heat is lost, causing particles to lose energy and arrange into a fixed structure.
Evaporation
The change of state from liquid to gas occurring at the surface of the liquid as particles gain enough energy to escape.
Boiling
The rapid change of state from liquid to gas that occurs when a liquid is heated to its boiling point.
Example: Water boiling at 100°C
Condensation
The change of state from gas to liquid as gas particles lose energy and come closer together.
Example: Water vapor condensing on a cold window
Sublimation
The direct change of state from solid to gas without passing through the liquid state, as particles gain enough energy to separate.
Deposition
The direct change of state from gas to solid without passing through the liquid state, as particles lose energy and settle into a solid form
Soild–> Liquid
When solid reaches the melting point it reaches a state of plateu because the energy added during this stage is to break the interparticle forces not raise kenetic energy
