| A | B |
|---|
| nucleus | central core of an atom |
| atomic number | equals the number of protons |
| proton | has a positive electrical charge |
| neutron | has no electrical charge |
| electron | has a negative electrical charge |
| compound | made up of atoms of tow or more elements |
| chemical reaction | combining in ways that cause atoms to become stable |
| molecule | the simplest part of a substance |
| ion | an atom or molecule with an electrical charge |
| ionic bond | the formation between a negative and positive charge. |
| energy | the ability to do work |
| free energy | the endergy in a system that is available for work |
| reactants | shown on the left side of a reaction equation |
| products | shown on the right side of a reaction equation |
| exergonic | chemical reactions that involve a net release of free energy |
| endergonic | reactions that involve a net absorbtion of free energy |
| activation energy | the minimum amount of energy needed to start a reaction |
| catalysts | reduce the amount of activation energy |
| enzymes | importan catalysts in living things |
| oxidation | loses one or more electrons |
| reduction | gains one or more electrons |
| solution | mixture with one or more substances uniformly distributed |
| solute | the substance being dissolved |
| solvent | the substance doing the dissolving |
| concentration | measure of the amount of solute dissolved in a fixed amount of solvent |
| saturation | cannot hold no more solute |
| aqueous solution | water is the solvent |
| dissociation | the breaking apart of water |
| hydroxide ion | OH- |
| hydronium ion | H3O+ |
| acid | H30+ greater than OH- |
| base | OH- greater than H3O+ |
| neutral solution | H3O+ equals OH- |
| pH scale | 0-14 compoaring relative concentrations of hydronium and hydroxide ions. |
| buffers | chemical substance that neutralize small amont of either an acid or base |
