| A | B |
|---|
| atom | the simplest particle of an element that retains all of the properties |
| atomic number | the number of protons in an atom |
| bond | in chemical reactions, chemical bonds are broken, atoms are rearranged |
| chemical reaction | combining in ways that cause their atoms to become stable |
| compound | a pure substance that is made up of atoms of two or more elements |
| covalent bond | forms when two atoms share one or more pairs of electrons |
| electron | high-energy particles with very little mass |
| element | pue substances that cannot be broken down chemically into simpler kinds of matter |
| energy level | they move about the nucleus at very high speeds |
| ion | an atom or molecule with an electrical charge |
| ionc bond | postive and negative charges attract each other |
| mass | the quantity of matter an object has |
| matter | anything that occupies space and has mass |
| molecule | the simplest part of a substance that retains all of the properties of the substances and that can exist in a free state |
| neutron | has no electrical charge |
| nucleus | the central core of an atom consists of two kinds of paricles |
| proton | has a positive charge |
| activation energy | the amount of energy needed to start the reaction |
| catalyst | reduce the amount of activation energy that is needed for a reaction |
| endergonic reaction | reactions that involve a net abosorption of free energy |
| energy | the ability to do work or cause change |
| enzyme | important class of catalyst in living things |
| exergonic reaction | chemical reactions that involve a net release of free energy |
| free energy | the energy in a system that is available for work |
| oxidation reaction | a reactant loses one or more electrons |
| product | a compound formed by a chemical reaction |
| reactant | a compound or atom involved in a chemical reaction |
| redox reaction | a reduction-oxidation reaction in which electrons are transferred between atoms |
| reduction reaction | a chemical reaction in which a reactant gains one or more electrons, beoming more negative in charge |
| state | the rate at which atoms or molecules of a substance move |
| acid | any substance that increases the concentration of hydrogen ions when added to a water solution |
| alkaline | referres to bases |
| aqueous solution | a solution in which water is the solvent |
| base | any substance that increases the concentration of hydroxide ions when added to a water solution |
| buffer | a chemical that neutralizes small amounts of acids or bases added to a solution |
| concentration | a measurment of the amount of solute dissolved in a fixed amount of solvent |
| dissociation | the separting of a molecule into simpler molecules, atoms, radicals, or ions |
| hydronum ion | the H3O+ ion |
| hydroxide ion | the OH- ion |
| pH scale | a numreic range that quantifies the relative concentration of hydronuim ions and hydroxide ions in a solution |
| saturated solution | a solution in which no more solute can dissolve |
| solute | a substance dissolved in a solution |
| solution | a mixture in which one or more substances are uniformly dissolved in another substance |
| solvent | a solution, the substance in which solute is dissolved |
