| A | B |
|---|
| Matter | anything that occupies space and has mass. |
| Mass | the quanity of matter an object has. |
| Elements | pure substances that cannot be broken down chemically into simpler kinds of matter. |
| atoms | simplest particle of an element that retains all the properties of that element. |
| atomic number | the number of protons in an atom. |
| atomic mass | The number of protons and neutrons in an atom. |
| atomic nucleus | central core of an atom. |
| electron cloud | region of an atom where electroms are found |
| proton | positively charged particle found in the nucleus of an atom. |
| neutron | a neutral particle found in the nucleus of an atom. |
| electron | negatively charged particles surrounding the nucleus of an atom. |
| Compound | a pure substance that is made up of two or more different kinds of atoms chemically combined. |
| molecule | two or more atoms chemically combined |
| covalent bond | a chemical bond in which atoms share electrons |
| ionic bond | a chemical bond in which electron(s) are transfered from one atom to another. |
| ion | an atom or molecule with an electrical charge. |
| energy | the ability to do work or transfer heat. |
| work | force X distance |
| reactants | chemicals found on the left side of a equation. |
| products | chemicals found on the right side of an equation. |
| exergonic reaction | chemical reactions that involve the net release of energy. |
| endergonic reactions | reactions that involve a net absorption of free energy. |
| free energy | energy in a system available to do work |
| potential energy | stored energy |
| kinetic energy | energy in motion |
| activation energy | the amount of energy needed to start a chemical reaction. (release potential energy) |
| catalyst | chemical substances that reduce the amount of activation energy needed for a reaction. |
| enzymes | an important group of catalysts in living things |
| mixtures | physical combinations of two or more substances. |
| solutions | mixtures in which one substance dissolves in another substabce |
| suspensions | mixtures in which one substance separates for the other over time.(settles out) |
| colloids | mixtures in which a substance remains suspended and does not settle out over time |
| solute | the substance that is dissolved in the solution. |
| solvent | the substance in which another substance is dissolved. |
| sol | the liquid phase of a colloid |
| gel | the semi-solid phase of a colloid |
| acid | a solution in which the number of hydronium ions is greater than the number of hydroxide ions. |
| base | a solution in which the number of hydroxide ions is greater than the number of hydronium ions. |
| buffers | chemical substances that neutralize small amounts of either an acid or a base when added to solution. |
| concentration | a measure of the amount of solute dissolved in a fixed amount of solvent |
| hydroxide ion | OH- |
| hydronium ion | H30+ |
| aqueous solutions | solutions in which water is the solvent. |
| oxidation reaction | when a reactant losses one or more electrons becoming positive in charge. |
| reduction reaction | when a reactant gains one or more electrons becoming negative in charge |
| redox reactions | reactions in which electrons are transfered between atoms. |
