Matter & Change

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Matter
Anything that has mass and occupies space
Volume
The amount of three-dimensional space an object occupies.
Weight
A measure of the gravitational pull on Matter.
Atom
The smallest unit of an element that maintains the properties of that element.
Molecule
A neutral group of atoms held together.
Elements
A pure substance made of only one kind of atom. A substance that cannot be broken down into other substances by ordinary means.
Compound
A substance made up of two or more elements chemically combined. A substance that can be broken down into simpler substances.
Mixture
A combination of two or more substances that are not chemically combined.
Homogeneous
A mixture with uniform characteristics throughout.
Heterogeneous
A mixture that has parts with different compositions; it is not uniform throughout the mixture.
Filtration
The process of passing a mixture through a porous device, such as filter paper, to separate one component from another.
Evaporation
If a salt-water solution was allowed to stand, the water would evaporate and leave behind the crystals of salt.
Decanting
If the solid particles of a liquid mixture settle to the bottom of the container, the liquid can be carefully poured off.
Centrifuge
The centrifuge spins rapidly which causes the solids to settle to bottom of the container.
Paper Chromatography
Separates mixtures of dyes or pigments because the different substances will move at different rate on the paper.
Solid
Has a definite volume and a definite shape.
Liquid
Has a definite volume but no definite shape. Assumes the shape of the container.
Gas
Has neither a definite shape or volume.
Property
A characteristic that defines an entire group of substances.
Extensive properties
Depend on the amount of matter. These properties include volume, mass, or weight, or amount of energy in a substance.
Intensive properties
Do not depend on the amount of matter. These properties include melting point, boiling point, density, and the ability to conduct heat or electricity. These properties are the same for a given substance regardless of how much of the substance is present.
Physical Property
Can be observed or measured without changing the identity of the substance. Describes the substance itself, rather than describing how it can change into other substances during chemical reactions. Examples: color, odor, taste, hardness, density, melting point, boiling point,
Chemical Property
A characteristic that describes how the substance interacts with other substances to produce new substances.
Physical Change
A change in physical properties, but there is no change in the substances' chemical properties or chemical composition. No new substance is formed. It is a change from one phase of matter to another.
Chemical Change
Results in the production of one or more new substances that differ in chemical properties and composition from the original substance.
Reactants
The original substances participating in the chemical reaction.
Products
The new and different substances formed as a result of a chemical change.
Conservation of Mass
Matter cannot be created or destroyed by chemical change. During any chemical reaction, the quantity of matter remains unchanged. The mass of the products is always equal to the mass of the reactants.
Density
A measure of how much mass of a substance occupies a certain volume. Equation:
D=M / V