Term | Definition |
Matter | Anything that has mass and takes up space |
Chemistry | The study of the properties of matter |
Substance | A single kind of matter that is pure and has a specific set of properties |
Physical Property | A characteristic of a pure substance the can be observed without changing it into another substance |
Chemical Property | A characteristic of a pure substance that describes its ability to change into a different substance |
Element | A pure substance that cannot be broken down into other substances by physical or chemical means |
Atom | The basic particle of a substance |
Chemical Bond | The force that holds two atoms together |
Molecule | A particle made of two or more atoms chemically bonded together |
Compound | A pure substance made of two or more elements chemically combined |
Chemical Formula | A formula that gives the elements in a compound and the ratio of atoms |
Mixture | Two or more substances that are mixed together but not chemically combined |
Heterogeneous Mixture | A mixture in which pure substances are unevenly distributed throughout the mixture (can see the different parts) |
Homogeneous Mixture | A mixture in which substances are evenly distributed throughout the mixture (cannot see different parts) |
Solution | An example of a homogeneous mixture; forms when substances dissolve |
Weight | A measure of the force of gravity on an object. Changes with location. |
Mass | The measure of the amount of matter in an object. Does not change with location.
(M= d*v) |
SI System | The system of units used by scientists to measure the properties of matter |
Volume | The amount of space that matter occupies (v= l*w*h) |
Density | The measurement of how much mass of a substance in contained in a given volume
(D= m/v) |
Physical Change | A change in a substance that does not change its identity |
Chemical Change | A change in which one or more substances combine or break apart to form new substances |
Law of Conservation of Mass | The principal that the total amount of matter is neither created nor destroyed during any physical or chemical change |
Energy | The ability to do work or cause change |
Temperature | The measure of the average energy of motion of the particles of a substance |
Thermal Energy | The total energy of all the particles of an object |
Endothermic Change | A change in which energy is taken in |
Exothermic Change | A change in which energy is given off. |