Chemistry - Ch 7 Flashcards
Valence orbitals
occupied orbitals that hold the electrons involved in bonding
Effective nuclear charge
net electric field as if it results from a single positive charge located at the nucleus (Z subscript eff)
Bonding atomic radius (covalent radius)
distances separating the nuclei of atoms when they are chemically bonded to each other
Isoelectric series
group of ions all containing the same number of electrons
Ionization energy
minimum energy required to remove an electron from the ground state of the isolated gaseous atom or ion
Electron affinity
the energy change that occurs when an electron is added to a gaseous atom
Metallic character
the more an element exhibits the physical and chemical properties of metals, the greater its MC; MC generally increases as we proceed down a column of the periodic table
Alkali metals
Group 1A of periodic table; soft metallic solids; silvery metallic luster, high thermal/electrical conductivities; “alkali” = ashes; low densities & melting points; exist in nature only in compounds; react vigorously with water, producing hydrogen gas and a solution of an alkali metal hydroxide; reactions very exothermic; extremely reactive toward water and oxygen; usually stored submerged in a liquid hydrocarbon (mineral oil, kerosene)
Alkaline earth metals
Group 2A of periodic table; solids at room temp; typical metallic properties; harder, more dense than alkali metals, melt at higher temps; low 1st ionization energies (not as low as alkali metals); less reactive than alkali metals (Be & Mg, lightest of group, are least reactive); trend of increasing reactivity within the group; tend to lose their 2 outer s electrons to form 2+ ions; heavier AEM give off characteristic colors when strongly heated in a flame (calcium = red; strontium = crimson; barium = green)
Hydride ion
H-; a hydrogen atom that has gained an electron
O2-
superoxide ion
ozone
O3
allotropes
different forms of the same element in the same state
halogens
group 7A; “salt formers”; typically nonmetals; melting/boiling points increase with increasing atomic number; consists of diatomic molecules (F2, Cl2, Br2, I2); Fluorine gas is pale yellow; chlorine gas is yellow-green; bromine liquid is reddish brown; solid iodine is grayish black; highly negative electron affinities; tendency to gain electrons from other elements to form halide ions, X- (X = any of the halogen elements)
noble gases
group 8A; nonmetals that are gases at room temp; monatomic; have completely filled s and p subshells; large 1st ionization energies (decrease as you move down the column); stable electron configurations –> exceptionally unreactive; AKA inert gases;