Gr. 8 Properties of Matter

Chemistry
The study of the properties of matter and how matter changes.

Solid
Has a definite volume; definite shape; particles tightly packed and held together in fixed positions.

Gas
No definite shape, no definite volume; fills all available space in a container; is a fluid

Mixture
Two or more substances mixed together, but not chemically combined; can be separated; ex. Chex Mix

Solutions
A well mixed mixture containing a solvent and at least one solute that has the same properties throughout.
Ex. sugar dissolved in water is a solution.

Matter
Anything that takes up space and has mass.

Liquid
Has a definite volume; takes the shape of its container; called a fluid; particles touching, but can move around each other

Pure substance
A single kind of matter that has a specific set of properties. Ex. table salt

Element
A pure substance that can not be broken down into anything simpler by chemical or physical means. Ex. anything on the Periodic Table such as Gold, Oxygen, etc.

Viscosity
A liquid’s resistance to flowing; the lower the viscosity, the quicker the flow. Water has a low viscosity; Honey has a high viscosity

Chemical Change
A change in matter that produces one or more new substances; you can’t get the original substance back;
ex. rusting, photosynthesis, burning

Crystalline Solid
A solid that is made up of crystals arranged in a regular repeating pattern. Ex. salt, snow, sugar, quartz

Heterogeneous mixture
A mixture in which pure substances are unevenly distributed throughout the mixture. Ex. salad

Condensation
A change in state from a gas to a liquid state of matter; ex. fog, clouds, bathroom mirror after shower

Sublimation
When a solid goes directly to the gas state without passing through the liquid state; Ex. ice cubes shrinking in the freezer

Vaporization
The process of a liquid changing state into a gas; Two types: Evaporation and Boiling

Solvent
The part of the solution that dissolves the other substance

Physical Change
A change in matter that alters the appearance of matter, but does not make it a different substance; Ex. bending, dissolving, changing state, crushing. It remains the same substance, even though it looks different; broken glass is still glass

Amorphous Solid
A solid made up of particles that are not arranged in a regular pattern; they do not melt at a distinct temperature; Ex. plastic, butter

Homogeneous Mixture
A solution in which substances are so evenly mixed, you can’t tell them apart; ex. Kool-aid in water; hot chocolate

Law of Conservation of Matter/Mass
States that matter cannot be created or destroyed in any physical or chemical change; it can only be rearranged

Evaporation
A type of vaporization that takes place only on the surface of a liquid; ex. a rain puddle shrinking

Boiling
A type of vaporization that takes place throughout the liquid; Ex. Soup boiling in a pot on the stove. The bubbles you see is the liquid turning into a gas throughout the soup! Heat is required for boiling.

Solute
The part of the solution that is dissolved by the solvent; usually a solid, but may be a gas. Ex. the salt in ocean water is the solute

Saturated Solution
A mixture that contains as much dissolved solute as possible at a given temperature

Insoluable
Something that cannot dissolve

Compound
A pure substance made up of two or more elements chemically combined; CO2, H2O

Super Saturated Solution
Heating a saturated solution so that even more solute can dissolve in it.

Chemical Property of Matter
A characteristic of a pure substance that describes its ability to change into a different substance.
Ex. Flammability; reactivity; rusting, tarnishing

Physical Property of Matter
A characteristic of a pure substance that can be observed without changing it into another substance (e.g. density, melting point, texture, color, flexibility)

Melting
The change in state from a solid to a liquid; Melting Point is a characterist property of a substance. Ex. ice turning to water

Freezing
The change in state from a liquid to a solid; Ex.water turning to ice

Suspension
A mixture whose particles can be seen and easily separated; Ex. sand in water

Filter
To separate a mixture by using filter paper or a sieve

Solubility
How well a solute dissolves at a given temperature

Filtrate
The material that is filtered out and remains in the filter paper. Ex. coffee grounds

Decanting
Pouring off the liquid; Ex. Draining a can of tuna is decanting

Separation using vaporization
Evaporating or boiling off a liquid to get the other substances out of a solution

Distillation
The process of tuning water into water vapor and then condensing it back into a liquid by cooling the vapor.(condensation) Distillation must take place in a closed system so all the water can be recovered.

Water Cycle
Recycles all the water on Earth;has no beginning or end; sun is the source of energy that drives the water cycle

Transpiration
Water vapor given off through the leaves of plants

Precipitation
Any form of water that falls from the sky; rain, snow, sleet, hail

Runoff
Precipitation that “runs off” into bodies of water such as lakes, rivers or oceans

Groundwater
Precipitation that seeps into the cracks and spaces in soil and rock layers

% of water on Earth that has salt in it
About 97% (96.5%)

% of water on Earth that is fresh
About 3% (2.5%)

% of FRESH water on Earth that is actually drinkable
Less than .5%

% of the Earth’s surface that is covered by water
71% or close to 3/4ths of the Earth’s surface

The universal solvent
Water is the universal solvent because more things dissolve in it than anything else

Ways to speed up the rate of dissolving
Stir it; Shake it; Heat it; Make the particles of solute smaller by crushing