| A | B |
|---|
| A shorthand way to write the name of an element | Chemical Symbol |
| The positively charged center of an atom | Nucleus |
| A negatively charged particle that orbits around the nucleus of an atom | Electron |
| A particle in the nucleus of an atom that has a positive charge | Proton |
| A particle in the nucleus of an atom that has no electrical charge | Neutron |
| The number of protons in an atom's nucleus | Atomic number |
| The space where electrons most probably exist around the nucleus of an atom | Electron cloud |
| A very small particle of matter that makes up protons and neutrons | Quarks |
| Total particles in an atom's nucleus | Mass number |
| Atoms of the same element that have different numbers of neutrons | Isotopes |
| A table of the elements, in order by increasing atomic mass, arranged in rows and columns to show their repeated properties | Periodic table |
| One of the 18 vertical columns in the periodic table | Group |
| A diagram of an atom, using the element symbol with dots to show the electrons in the outer energy level | Dot diagram |
| A horizontal row of elements in the periodic table; increasing from left to right is the number of electrons in the atoms' outer shell | Period |
| An element usually having the following characteristics: shiny, ductile, and a good conductor of heat and electricity | Metals |
| An element that usually lacks the characterics of a metal | Nonmetal |
| An element having some properties of both a metal and a nonmetal | Metalloid |
| an atom or group of atoms that is electrically charged | ion |
| the attraction between two oppositely charged ions | Ionic bond |
| an ion that is made of more than one atom | Polyatomic ion |
| an orderly, three-dimensional pattern of ions or atoms in a solid | Crystal |
| a chemical bond formed when two atoms share electrons | Covalent bond |
| a chemical bond formed when two atoms share two pairs of electrons with each other | Double bond |
| a compound consisting of molecules of covalently bonded atoms | Molecule |
| the description of a covalent bond in which electrons are shared unequally, or of a molecule containing polar bonds that do not cancel out | Polar |
| the description of a covalent bond in which electrons are shared equally, or of a molecule containing nonpolar bonds or polar bonds that cancel out | Nonpolar |
| a naturally occurring solid that has a crystal structure and a definite chemical composition; a simple element, which is not organic, that is needed by the body | Mineral |
| The state in which one object's distance from another is changing. | motion |
| A place or object used for comparison to determine if an object is in motion. | reference point |
| The distance an object travels in one unit of time. | speed |
| Speed in a given direction. | velocity |
| The steepness, or slant of a line on a graph. | slope |
| The rate at which velocity changes. | acceleration |
| One of the major pieces that make up Earth's upper layer p. 296 | plate |
| Term used to describe a relationship between variables whose graph is a straight line p. 306 | linear |
| Term used to describe a relationship between variables whose graph is not a straight line p. 306 | nonlinear |
| Base unit of length in the System International | meter |
| a short, easy way to show a chemical reaction, using symbols instead of words | Chemical equation |
| a number in a chemical formula that tells the number of atoms in a molecule or the ratio of elements in a compound | Subscript |
| a substance that enters into a chemical reaction | Reactants |
| a substance formed as a result of a chemical reaction | Products |
| the principle stating that matter is not created or destroyed during a chemical reaction | Conseravtion of Mass |
| a number placed in front of a chemical formula in an equation that indicates how many atoms or molecules of each reactant and product are involved in a reaction | Coefficient |
| a chemical reaction in which two or more simple substances combine to form a new, more complex substance | Synthesis |
| a chemical reaction that breaks down a compound into simpler products | Decomposition |
| a substance that enters into a chemical reaction | Replacement reaction |
| the minimum amount of energy needed to start a chemical reaction | Activation energy |
| the amount of one material dissolved in a given amount of another material | Concentration |
| a material that increase the rate of a chemical reaction by lowering the activation energy | Catalyst |
| a biological catalyst that lowers the activation energy of reactions in cells | Enzyme |
| a material that decreases the rate of a reaction | Inhibitor |
| a rapid reaction between oxygen and fuel that produces thermal energy | Combustion |
| a material that releases energy when it burns | Fuel |
| a mixture in which particles can be seen and easily separated by settleing or filtration | Suspension |
| a very well-mixed mixture, having the same properties throughout | Solution |
| the part of a solution that is present in the largest amount and dissolves a solute | Solvent |
| the part of a solution present in a lesser amount and dissolved by the solvent | Solute |
| a mixture with small undissolved particles that do not settle out | Colloid |
| a mixture that has only a little solute dissolved in it | Dilute Solution |
| a mixture that has a lot of solute dissolved in it | Concentration solution |
| a measure of how well a solute can dissolve in a solvent at a given temperature | Solubility |
| a mixture that contains as much solute in it as possible at a given temperature | Saturated solution |
| a mixture in which more of the same solute can be dissolved | Unsaturated solution |
| a mixture that has more dissolved solute than is predicted by its solubility at the given temperature | Supersaturated solution |
| a substance that tastes sour, reacts with metals and carbonates, and turns blue litmus red | Acid |
| a compound that changes color when in contact with an acid or a base | Indicator |
| a substance that tastes bitter, feels slippery, and turns red litmus blue | Base |
| a positively charged ion (H+) | Hydrogen ion |
| a negatively charged ion (OH-), found in alcohols | Hydroxide ion |
| a range of values from 0 to 14 that expresses the concentration of hydrogen ions in a solution | pH scale |
| a reaction between an acid and a base | Neutralization |
| an ionic compound that can form from the neutralization of an acid with a base | Salt |
| the process that breaks down complex molecules of food into smaller molecules | Digestion |
| the physical process that tears, grinds, and mashes large food particles into smaller ones | Mechanical digestion |
| the process that changes large food molecules into smaller molecules | Chemical digestion |
| rainwater that is more acidic than normal rainwater | Acid rain |
