37 terms

Chapter 2 Vocab

anything that takes up space and has mass
substance that cannot be broken down to any other sunstance by chemical reactions
substance consisting of two or more different elements combined in a fixed ratio
Essential Elements
chemical element required for an organism to survive, grow, and reproduce
Trace Elements
element indispensable for life but required in extremely minute amounts
smallest unit of matter that retains the properties of an element
subatomic particle having no electrical charge its neutal and is found in the nuvleus of an atom
sunatomic particle with a single positive electrical charge, found in the nucleus of a atom
subatomic particle with a single negative charge one or more move around the nucleus of an atom
Atomic Nucleus
stoms sense central core, containing protons and neurons
measure of mass for atoms and subatomic partiles
Atomic Number
number of protons in a nucleus of a atom
Mass Number
sum of the number of protons and neutrons in an atoms nucleus
Atomic Mass
total mass of an atom
radioactive Isotope
isotope that is unstable; the nucleus decays spontaneously, giving off detectable particles and energy
one of several atomic forms of an element, each with the same number of protons but a different number of neutrons
Capacity to cause change, especially to do work (move matter against opposing forces)
Potential energy
energy that matter possesses as a result of its location or spatial arrangement
Electron shell
energy level of electrons ay a characteristic distance from the nucleus of an atom
Valence Electron
electron in the outermost electron shell
Valence shell
otermost energy shell of an atom, containing valence electrons involved in the chemical reactions of that atom
three-dimensional space where an electron is found 90% of the time
Chemical bonds
attraction between two atoms, resulting from sharing of outer-shell electrons or the presence of opposite charges on the atoms.
Covalent bond
type of strong chemical bond where two atom share one or more pairs of valence electrons
single bond
single covalent bond sharing of a pair of valence electrons by two atoms
double bond
double covalent bond, sharing two pairs of valence electrons by two atoms
atom or group atoms that gained or lost more elctrons, thus acquiring a charge
positively charged ion
negatively charged ion
ionic bond
chemical bond resulting from the attraction between oppositely charged ions
ionic compunds
compound resulting from the formation of an ionic bond also called salt
Hydrogen bond
weak chemical bond that is formed when the slightly + hydrogen atom of a polar coalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule or in another region of the same molecule
Van der Waals Interaction
weak attractions between molecules or parts of molecules that result from transient local partial charges
Chemical reaction
making and breaking of chemical bonds, leading to charges in the compostion of matter
starting material in a chemical reaction
material resulting from a chemical reaction
Chemical equilibrium
chemical reaction, state where the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentration of the reactants and products do not change with time