| A | B |
|---|
| atom | the basin unit of matter |
| nucleus | the center of an atom, which contains the protons and neutrons |
| electron | negatively charged particle; located in the space surrounding the nucleus |
| element | pure substance that consists entirely of one type of atom |
| isotope | one of several forms of a single element, which contains the same number of protons but different numbers of neutrons |
| compound | substance formed by the chemical comdination of two or more elements in definite proportions |
| ionic bond | chemical bond formed when one or more electrons are transferred from one atom to another |
| ion | atom that has a positive or negative charge |
| covalent bond | type of bond between atoms in which the electrons are shared |
| molecule | smallest unit of most compounds that displays all the properties of that compound |
| van der Waals forces | slight attraction that develops between oppositely charged regions of nearby molecules |
| hydrogen bond | weak attraction between a hydrogen atom and another atom |
| cohesion | atrraction between molecules of the same substance |
| adhesion | force of attraction between different kinds of molecules |
| mixture | material composed of two or more elements or compounds that are physically mixed together but not chemically combined |
| solution | type of mixture in which all the components are evenly distributed |
| solute | substance that is dissolved in a solution |
| solvent | dissolving substance in a solution |
| suspension | mixture of water and nondissolved material |
| pH scale | scale with values from 0 to 14, used to measure teh concentration of H+ ions in a solution |
| acid | compound that forms hydrogen ions (H+) in solution; a solution with a pH of less than 7 |
| base | compound that produces hydroxide ions (OH-) in solution; solution with a pH base of more than 7 |
| buffer | compound that prevents sharp, sudden changes in pH |
| monomer | small chemical unit that makes up a polymer |
| polymer | molecules composed of many monomers; makes up macromolecules |
| carbohydrate | compound made up of carbon, hydrogen, and oxygen atoms |
| monosaccharide | simple sugar molecule |
| lipid | macomolecule made mostly from carbon and hydrogen atoms; includes fats, oils, and waxes |
| nucleic acid | macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus |
| nucleotide | subunit of which nucleic acid acids are composed; made up of a 5-carbon sugar, phosphate group, and a nitrogenous base |
| protein | macromolecule that contains carbon, hydrogen, and nitrogen |
| amino acid | compound with an amino group on one end and a carboxyl group on the other end |
| chemical reaction | process that changes, or transforms, one set of chemicals into another set of chemicals |
| reactant | elements or compounds that enter into a chemical reaction |
| product | elements or compounds produced by a chemical reaction |
| activation energy | energy that is needed to get a reaction started |
| catalyst | substance that speeds up the rate of a chemical reaction |
| enzyme | protein catalyst tht speeds up the rate of specific biological reactions |
| substrate | reactant of an enzyme-catalyzed reaction |
