Chapter 2: The Chemical Context of Life Flashcards

7534368951	Matter	anything that takes up space and has mass	0
7534368952	Element	any substance that cannot be broken down to any other substance	1
7534368953	Compound	a substance consisting of two or more elements in a fixed ratio	2
7534368954	Trace Elements	an element indispensable for life but required in extremely minute amounts	3
7534368955	Atom	the smallest unit of matter that retains the properties of an element	4
7534368956	Neutron	an electrically neutral particle (a particle having no electrical charge), found in the nucleus of an atom	5
7534368957	Electron	a subatomic particle with a single negative charge; one or more electrons move around the nucleus of an atom	6
7534368958	Proton	a subatomic particle with a single positive electrical charge, found in the nucleus of an atom	7
7534368959	Atomic Nucleus	an atom's central core, containing protons and neutrons	8
7534368960	Atomic Number	the number of protons in the nucleus of an atom, unique for each element and designated by a subscript to the left of the elemental symbol	9
7534368961	Atomic Mass; Atomic Weight	the total mass of an atom, which is the mass in grams of one mole of the atom	10
7534368962	Mass Number	the sum of the number of protons and neutrons in an atom's nucleus	11
7534368963	Dalton	a measure of mass for atoms and subatomic particles	12
7534368964	Isotope	one of several atomic forms of an element, each containing a different number of neutrons and thus differing in atomic mass	13
7534368965	Radioactive Isotope	an isotope that is unstable; the nucleus decays spontaneously, giving off detectable particles and energy	14
7534368966	Energy	the capacity to do work (to move matter against an opposing force)	15
7534368967	Energy Levels	the different states of potential energy for electrons in an atom	16
7534368968	Potential Energy	the energy stored by matter as a result of its location or spatial arrangement	17
7534368969	Electron Shell	an energy level representing the distance of an electron from the nucleus of an atom	18
7534368970	Valence Shell	the outermost energy shell of an atom, containing the valence electrons involved in the chemical reactions of that atom	19
7534368971	Valence Electrons	the electrons in the outermost electron shell	20
7534368972	Orbital	the three-dimensional space where an electron is found 90% of the time	21
7534368973	Molecule	two or more atoms held together by covalent bonds	22
7534368974	Single Bond	a chemical bond in which one pair of electrons is shared between two atoms	23
7534368975	Chemical Bond	an attraction between two atoms resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms; the bonded atoms gain complete outer electron shells	24
7534368976	Double Bond	a chemical bond in which two pairs of electrons are shared between two atoms	25
7534368977	Nonpolar Covalent Bond	a chemical bond in which two pairs of electrons are shared between two atoms	26
7534368978	Polar Covalent Bond	the shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive	27
7534368979	Valence	the bonding capacity of an atom generally equal to the number of unpaired electrons in the atom's outermost shell	28
7534368980	Electronegativity	the attraction of an atom for the electrons of a covalent bond	29
7534368981	Cation	an ion with a positive charge, produced by the loss of one or more electrons	30
7534368982	Anion	a negatively charged ion	31
7534368983	Ion	an atom that has gained or lost electrons, thus acquiring a charge	32
7534368984	Ionic Bond	a chemical bond resulting from the attraction between oppositely charged ions	33
7534368985	Ionic Compound	compounds resulting from the formation of ionic bonds; a salt	34
7534368986	Hydrogen Bond	a type of weak chemical bond formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule	35
7534368987	Structural Formula	a type of molecular notation in which the constituent atoms are joined by lines representing covalent bonds	36
7534368988	Molecular Formula	a type of molecular notation indicating only the quantity of the constituent atoms	37
7534368989	van der Waals interactions	weak attractions between molecules or parts of molecules that are brought about by localized charge fluctuations	38
7534368990	Chemical Reactions	a process leading to chemical changes in matter; involves the making and/or breaking of chemical bonds	39
7534368991	Reactant	a starting material in a chemical reaction	40
7534368992	Product	an ending material in a chemical reaction	41
7534368993	Chemical Equilibrium	in a reverse chemical reaction, the point at which the rate of the forward reaction equals the rate of the reverse reaction	42