Matter & Energy Chapter 2 - Kory Parsia

density

A property of matter representing the mass per unit volume

physical change

a change in a substance that does not change the substance into a different one

chemical change

A change of one substance into another substance

melting

The process by which a substance changes from its solid state to its liquid state

melting point

the temperature at which a substance changes from its solid state to its liquid state through melting

freezing

the process by which a substance changes from its liquid state into its solid state

freezing point

the temperature at which a substance changes from its liquid state to its solid state through freezing

evaporation

a process by which a substance changes from its liquid state to its gas state by random particle movement. Evaporation usually occurs at the surface of a liquids over a wide range of temperatures

sublimation

the process by which a substance changes directly from its solid state to its gas state without becoming a liquid first

boiling

a process by which a substance changes from its liquid state to its gas state. The liquid is heated to a specific temperature at which bubbles of vapor form within the liquid

boiling point

the temperature at which a substance changes from its liquid state to its gas state through boiling

condensation

the process by which a gas becomes a liquid

law of conservation of mass

a law stating that no matter how energy is tranferred or transformed, it continues to exist in one form or another

chemical reaction

the process by which chemical changes occur. In a chemical reaction, atoms are rearranged, and chemical bonds are broken and formed

chemical equation

a short way to show a chemical reaction using symbols instead of words

coefficient

the number before a chemical formula that indicates how many molecules are involved in a chemical reaction

subscript

a number written slightly below and to the right of a chemical symbol that shows how any atoms of an element are in a compound

reactants

a substance that is present at the beginning of a chemical reaction and is changed into a new substance

products

a substance formed by a chemical reaction. A product is made by the rearrangement of atoms and bonds in reactants