| A | B |
|---|
| Ionic Bond | type of bond that gains electrons from another atom and loses electrons from its outer shell |
| Electrons | directly involved in chemical reactions between atoms; one of three atomic particles |
| Isotopes | hydrogen, deuterium, and tritium are examples of ______ |
| Gas | state of matter has no definite shape and no definite volume |
| Liquid | state of matter that has no definite shape but has a definite volume |
| Solid | state of matter has a definite shape and definite volume |
| Number of Naturally Occuring Elements | 92 |
| Number of Named Elements | 106 |
| pH5 is ___ more acidic than pH6. | 10 Times |
| Inductive Reasoning | reasoning based on observing and testing |
| Deductive Reasoning | reasoning based on facts or already established principles |
| SurfaceTension | measure of how difficult it is to stretch or break the surface of a liquid |
| Valence | bonding capacity of an atom equals the number of unpaired electrons in the outer shell |
| Molecular Formula | formula that indicates only the kinds an dnumbers of atoms in a molecule |
| Structural Formula | indicates both number and type of atoms and also the bonding within a molecule |
| Potential Energy | energy stored in matter as a consequence of the relative position of masses |
| Energy | ability to do work |
| Dalton | measurement unit for atomic mass |
| Reactant | starting material in chemical reaction |
| Chemical Reaction | process leading to chemical changes in matter; involves making and breaking of bonds |
| Acid Precipitation | rain, snow, etc. with pH below 5.6; damages or destroys organisms by acidifying lakes, streams, etc. |
| Buffers | chemical substance that reists changes in pH by accepting ions fromdonating H+ ions to solutions |
| Potential Hydrogen | pH- describes acidity of solution |
| Base | compound accepts H+ ions and removes them from solution |
| Acid | chemical compound that donates H+ ions to solutions |
| Solute | substance dissolved in a solution |
| Solvent | dissolving agent in a solution |
| Solution | fluid misture of two or more substances, consisting of a dissolving agent and solute |
| Temperature | measure of intensity of heat, reflecting average kinetic energy or speed of molecules |
| Heat | amount of energy associated with movement of atoms and molecules |
| Adhesion | tendency of different kinds of molecules to stick together |
| Cohesion | tendency of molecules of same kind to stick together |
| Hydrogen Bond | weak chemical bond formed when partially positive hydrogen atom is attracted to negative atom |
| Polar Molecule | molecule containing polar covalent bonds; has a slightly negative pole and two slightly postive ones |
| Polar Covalent Bond | chemical bond in which shared electrons pulled close to more electronegative atom, making it partially negative and the other partially positive |
| Oxygen | element considered most electronegative of all elements |
| Nonpolar Covalent Bond | attraction between atoms that share one or more paris of electrons equally because atoms have similar electronegativity |
| Electronegativity | tendency for an atom to pull electrons toward itself |
| Double Bond | type of covalent bond in which two atoms share two pairs of electrons |
| Molecule | two or more atoms held together by covalent bonds |
| Covalent Bond | strong chemical bond in which two atoms share one or more pairs of outer shell electrons |
| Chemical Bond | attraction between two atoms resulting from a sharing of outer shell electrons or presence of opposite charges on the atoms; bonded atoms gain complete outer electron shells |
| Ion | atom or molecule with electrical charge resulting from gain or loss of one or more electrons |
| Electron Shell | Energy level at which an electron orbits the nucleus of an atom |
| Radioactive Isotope | isotope whose nucleus decays spontaneously giving off particles and energy |
| Isotope | variant form of atom; have same number of protons but different number of neutrons |
| Mass Number | sum of numbers of protons and neutrons |
| Atomic Weight | approximate total mass of an atom |
| Atomic Number | number of protons in each atom of a particular element |
| Nucleus | atom's central core contains protons and neutrons |
| Neutron | subatomic particle that has a neutral charge and lives in the nucleus |
| Electron | subatomic particle with negative charge and lives outside the nucleus |
| Proton | subatomic particle found in the nucleus and has a positive charge |
| Atom | smallest unit of matter and named from Greek word meaning indivisible |
| Compound | substance containing two or more elements in a fixed ratio |
| CHON- Carbon, Hydrogen, Oxygen, Nitrogen | four elements essential to life; these four make up 96% of human body |
| Trace Elements | materials essential to some organisms but only in minute quantites |
| Chemical Element | substance that can't be broken down to other substances by ordinary chemical means |
| Matter | anything that occupies space and has mass |
