chemistry chapter 2 Flashcards
periodic law
which states that the chemical properties of the elements are dependent, in a systematic way, upon their atomic numbers
periods
rows. 7 of them, representing the principal quantum numbers n=1 to n=7, and each period is filled sequentially
groups
columns. Represent elements that have the same electronic configuration in their valence, or outermost shell, and share similar chemical properties
valence electrons
electrons in the outermost shell. Involved in chemical bonding and determine the chemical reactivity and properties of the element
representative elements
which have either s or p sublevels as their outermost orbitals. A elements
nonrepresentative elements
including transition elements, which have partially filled d sublevels, and the lanthanide and actinide series, which have partly filled f sublevels. B elements
atomic radius
of an element is equal to one-half the distance between the centers of two atoms of that element that are just touching each other
ionization energy (IE)
is the energy required to completely remove an electron from a gaseous atom or ion
first ionization energy
is the energy required to remove one valenece electron from the parent atom
second ioniztion energy
is the energy needed to remove a second valence electron from the univalent ion to form the divalent ion
electron affinity
is the energy change that occurs when an electron is added to a gaseous atom, and it represents the ease with which the atom can accept an electron
group IIA elements
alkaline earths, have low electron affinity values. Are relatively stable because their s subshell is filled
group VII elements
halogens, have high electron affinities because the addition of a electron to the atom results in a completely filled shell, which represents a stable electron configuration
group VIII elements
noble gases, have electron affinities on the order of zero, since they already possess a stable octet and cannot readily accept an electron
electronegativity
is a measure of the attraction an atom has for electrons in a chemical bond
metals
are shiny solids at room temperature, and generally have high melting points and densities
malleability
the ability of metal to be hammered into shapes
ductility
ability to be drawn into wires
nonmetals
are generally brittle in the solid state and show little or no metallic luster. They have high ionization energies and electronegativities, and are usually poor conductors of heat and electricity
metalloids
their densities, boiling points, and melting points fluctuate widely. Elements classified as metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium
alkali metals
are the elements of group IA. They posses most of the physical properties common to metals, yet their densities are lower than those of other metals. Have only one loosely bound electron in their outermost shell, giving them the largest atomic radii of all the elements in their respective periods
alkaline earths
are the elements of group IIA, which also possess many characteristically metallic properties. Have low electronegativities and positive electron affinities
halogens
group VIIA, are highly reactive nonmetals with seven valence electrons (one short of the favored octet configuration. The electronegativities are very high, and they are particularly reactive towards alkali metals and alkaline earths, which “want” to donate electrons to the halogens to form stable ionic crystals
noble gases
are found in group VIII. Are fairly nonreactive because they have a complete valence shell, which is an energetically favored arrangement. Gives them little to no tendency to gain or lose electrons, high ionization energies, and no real electronegativites. they possess low boiling points and are all gases at room temperature
transition elements
groups IB to VIIIB, are all considered metals. Are very hard and have high melting oints and boiling points
