Chapter 2 Flashcards
actinide
inner transition metal in the bottom of the bottom two rows of the periodic table
alkali metal
element in group 1
alkaline earth metal
element in group 2
alpha particle
positively charged particle consisting of two protons and two neutrons
anion
negatively charged atom or molecule (contains more electrons than protons)
atomic mass
average mass of atoms of an element
atomic mass unit (amu)
(also, unified mass unit, u, or Dalton, Da) unit of mass equal to 1/12 of the mass of a carbon-12 atom
atomic number (Z)
number of protons in the nucleus of an atom
binary acid
compound that contains hydrogen and one other element, bonded in a way that imparts acidic properties to the compound (ability to release H+ ions when dissolved in water)
binary compound
compound containing two different elements
cation
positively charged atom or molecule (contains fewer electrons than protons)
chalcogen
element in group 16
chemical symbol
one, two, or three letter abbreviation used to represent an element or its atoms
covalent bond
attractive force between the nuclei of a molecule’s atoms and pairs of electrons between the atoms
covalent compound
(also, molecular compound) composed of molecules formed by atoms of two or more different elements
Dalton (Da)
alternative unit equivalent to the atomic mass unit
Dalton’s atomic theory
set of postulates that established the fundamental properties of atoms
electron
negatively charged, subatomic particle of relatively low mass located outside the nucleus
empirical formula
formula showing the composition of a compound given as the simplest whole-number ratio of atoms
fundamental unit of charge
(also called the elementary charge) equals the magnitude of the charge of an electron (e) with e = 1.602 * 10^-19 C
group
vertical column of the periodic table
halogen
element in group 17