| A | B |
|---|
| substance | a type of matter with a fixed composition |
| element | all atoms have identity; a pure substance |
| compound | atoms of two or matters is combined in a fixed proportion |
| heterogeneous mixture | mixture in which particles are seen easily |
| homogeneous mixture | mixture in which particles are not seen easily |
| solution | a homogeneous mixture of particles so small that they cannot be seen with a microscope and will never settle the the bottom of their container |
| colloid | a type of mixture of particles that are larger than those in a solution but not heavy enough to settle out |
| Tyndall effect | the scattering of light by colloid particles |
| suspension | a heterogeneous mixture liquid of particles that will settle the the bottom of their container |
| physical property | any characteristic of a material that can be observed without change the identity of the substances that make up the material |
| physical change | a changes in size, shape or state of matter |
| distillation | the process of separating substance in a mixture by evaporating a liquid and recondensing the vapor |
| chemical property | a characteristic of a substance that indicates whether it can undergo a certain chemical change |
| chemical change | a change of one substance to another |
| law of conservation of mass | the mass of all substances that are present before a chemical change = the mass of all substances after the changes |
| kinetic theory | is an explanation of how particles in matter behave |
| melting point | temperature at which a solid begins to liquefy |
| heat of fusion | amount of energy required to change a substance form the solid phase to the liquid phase |
| boiling point | the temperature at which the pressure of the vapor in the liquid is waura to the eternal pressure acting on the surface of the liquid |
| heat of vaporization | the amount of energy required for the liquid at its boiling point ot become a gas |
| diffusion | spreading of particles throught a given volume until they are uniformly distributed |
| plasma | matter consisting of positively and negatively charged particles |
| thermal expansion | increae in the size a substance when the temperature is increased |
| buoyancy | ability of a fluid - liquid or gas - to exert an upward force on an object immersed in fluid |
| pressure | the amount of force exerted per unit area; SI unit is the Pa (pascal) |
| viscosity | a fluid's resistance to flow |
| First assumption of kinetic theory | All matter is composed of small particles (atoms, molecules, and ions) |
| Second assumption of kinetic theory | These particles are constant, random motion |
| Third assumption of kinetic theory | These particles are colliding with each other and the walls and their container |
| thermal energy | the total energy of a materials particles, including kinetic ÐÐ vibrations and movement within and between the particles -- and potential -- resulting from forces that act within or between particles |
| Amorphous Solids | have no definite melting point. They liquefy over a temperature range |
| Liquid Crystals | maintain some geometric order in the liquid state |
| Pascal | Pressure unit |
| Volume - Pressure Equation | P1V1 =P2V2 |
| Charles' Law | the volume of a gas increases with increasing temperature as long as the pressure doesn't change |
| Boyle's Law | that if lthe temperature I constant, as the voume of a gas decreases the pressure increases. That at a constant temperature, as the volume of a gas increases the pressure decreases |
| The Pressure - Temperature Relationship | This relationship describes how, at a constant volume, the pressure increases with increasing temperature. |
| atom | smallest piece of matter that still retains the propery of the element |
| nucleus | small, positively- charged center of an atom |
| proton | are particles with an electrical charge of 1+ |
| neutron | are neutral particles that do not have a charge |
| electron | are particles with an electrical charge of 1- |
| quark | smaller particles that make up protons and neutrons |
| electron cloud | the area around the nucleus of an atom where its electrons are most likely found |
| atomic number | the number of protons in an atom |
| mass number | the sum of the number of protons and neutrons in the nucleus of an atom |
| isotope | atoms of the same element that have different numbers of neutrons |
| average atomic mass | is the weighted-average mass of the mixture of its isotopes |
| periodic table | elements are arranged by increasing atomic number and by changes in physical and chemical properties |
| group | vertical columns in the periodic table |
| electron dot diagram | uses the symbol of an element and dots to represent the electrons in the outer energy level |
| period | horizontal rows of elements on the periodic table |
| Most of the mass of an atom | is contained in the nucleus |
| the mass of a proton and a neutron | are approximately equal |
| the mass of an electron | is neglibible when find the mass of an atom |
| atomic mass unit | unit of measurement for atomic particles |
| the carbon - 12 isotope | was used to define the amu |
| the number of protons | identifies the element |
| Medeleev | created the periodic table |
