Key terms REVIEW

IN YOUR GROUPS, SEE HOW MANY TERMS YOU CAN DEFINE… MatterChemistrySubstancePhysical property Chemical propertyElementAtom Chemical bond MoleculeCompoundChemical FormulaMixture HeterogeneousHomogeneousWeight Mass VolumeDensity Physical change Chemical change Law of Conservation of MassTemperature Thermal energyEndothermicExothermic Chemical energyPotential energyKinetic energy

MATTER Anything that has mass and takes up space…all of the stuff…it’s all matter

CHEMISTRY The study of matter and how matter changes

SUBSTANCE A single kind of matter that is pure…always has a specific composition

PHYSICAL PROPERTY A characteristic of a substance that can be observed without changing it into another substance

CHEMICAL PROPERTY A characteristic of a substance that describes its ability to change into difference substances

ELEMENT A substance that cannot be broken down into any other substances by chemical or physical means

ATOM The basic particle from which all elements are made

CHEMICAL BOND A force of attraction between two or more atoms

MOLECULE A group of two or more atoms held together by chemical bonds

COMPOUND A substance made of two or more elements that are chemically combined in a set ratio

CHEMICAL FORMULA Symbol representation showing the elements in compound and the ratio of atoms

MIXTURE Two or more substance that are together in the same place, but the atoms are not chemically bonded

HETEROGENEOUS Mixture where you can usually see the different parts and they are easily separated out

HOMOGENEOUS Mixture where the substances are evenly mixed so it is difficult to see the different parts

WEIGHT A measure of the force of gravity

MASS The amount of matter in an object

VOLUME The amount of space matter occupies

DENSITY A measure of the mass of a material in a given substance…how tightly packed matter is in an object

PHYSICAL CHANGE An alteration of the form or appearance of matter but does not turn any substance in the matter into a different substance

CHEMICAL CHANGE (REACTION) A change in matter that produces one or more new substances

LAW OF CONSERVATION OF MASS Matter cannot be created nor destroyed in any chemical or physical change

TEMPERATURE A measure of how hot or cold something is

THERMAL ENERGY The total energy of the motion of all of the particles in an object

ENDOTHERMIC A change in which energy is absorbed (gets cold )

EXOTHERMIC A change in which energy is released (gets hot)

CHEMICAL ENERGY The energy stored in the chemical bonds between atoms

POTENTIAL ENERGY Energy that is stored

KINETIC ENERGY Energy of motion and movement