click below
click below
Normal Size Small Size show me how
Chapter 2
Basic Chemistry
Term | Definition |
---|---|
molecule | the smallest particle of a substance that has all the properties of the substance |
atom | the basic unit of matter |
matter | anything that has mass and takes up space |
mass | the amount of material an object has |
diversity | differing from one another |
organization | the arrangement of parts into a whole |
molecular | related to molecules |
chemistry | the study of matter and how it changes |
chemical process | a rearrangement of atoms or molecules to produce one or more new substances with new properties |
bacteria | the simplest single cells that carry out all basic life activities |
physical property | a characteristic of a substance or an object that can be observed without changing the substance into a different substance |
chemical property | a characteristic that describes how a substance changes into a different substance |
element | a substance that cannot be separated into other kinds of substances |
chemical reaction | a chemical change in which elements are combined or rearranged |
chemical bond | the force holding atoms together in a compound or molecule |
element symbol | one, two, or three letters that represent the name of an element |
compound | a substance that is formed when atoms of two or more elements join together |
subatomic particle | a proton, neutron, or other particle smaller than the atom |
nucleus | an atom's center; made of protons and neutrons |
electron | a tiny particle in an atom that moves around the nucleus; it has a negative charge |
proton | a tiny particle in the nucleus of an atom; it has a positive electrical charge |
neutron | a tiny particle in the nucleus of an atom; it has the same mass as the proton, and no electrical charge |
electron cloud | the space effectively occupied by electrons in an atom |
atomic number | the number of protons in the nucleus of an atom |
atomic mass | the average mass of the atom of an element |
isotope | one of a group of atoms of an element with the same number of protons and electrons by different numbers of neutrons |
radioactive | the property of some elements or isotopes to give off energy as they change to another substance over time |
radioisotope | a radioactive isotope |
chemical formula | a set of symbols and subscripts that tell the kinds of atoms and how many of each kind are in a compund |
ion | an atom that has either a positive or a negative charge |
ionic compund | two or more ions held next to each other by electrical attraction |
empirical formula | the simplest formula for a compound |
radical | a group of two or more atoms that acts like one atom |
binary compund | a compound that contains two elements |
electron shell | a specific energy level which electrons orbit the nucleus |
covalent bond | a bond resulting from the sharing of one or more pairs of electrons between two atoms |
reactant | a substance that is altered in a chemical reaction |
product | a substance that is formed in a chemical reaction |
polar molecule | a molecule with an uneven distribution of electron density |
hydrogen bond | a weak electrical attraction between the slight positive charge on a hydrogen atom and a slight negative charge on another atom. |
solvent | a substance capable of dissolving one or more other substances |
hydrophillic | water-loving; polar molecules are hydrophillic |
crystalline | a substance with a regularly repeating arrangement of its atoms |
hydrophobic | water-hating; nonpolar molecules are hydrophobic |
acid | a substance that can donate a proton or accept and electron |
base | a substance that can accept a proton or donate and electron |
pH | a number that tells whether a substance is an acid or a base |
neutral solution | a solution that has a pH of 7; it is neither an acid nor a base |
buffer | a solution that can receive moderate amounts of either acid or base without significant change in its pH |
ionic bond | a type of bonding in which ions are held together by the strong attraction of their opposite charges |