Chapter 7 Flashcards
What are periods in the Periodic Table?
horizontal (left to right)
What are groups in the Periodic Table?
verticle (up and down)
What are valence orbitals?
occupied orbitals that hold valence electrons | elements in the same column/group have same #valence electrons
Who is Dmitri Mendeleev?
used chemcial properties to organize the table
Who arranged the elements based on weight?
Dmitri Mendeleev and Lothar Meyer
Who is Henry Mosely?
developed the concept of atomic number after Rutherford’s discovery of the nuclear atom
What is periodicity?
repetitive pattern of a property for elements based on atomic number
What is effective nuclear charge?
net positive charge experienced by an electron in an atom
What is the effective nuclear charge (Zeff) not the full nuclear charge?
the core (inner shell) electrons shield the valence (outer shell) electron from nucleus = valence e- experiences forces from core e- repulsion and nucleus attraction
What is the periodic TREND for effective nuclear charge?
increases left–>right | slight increases down a group
What are van der Waals radius?
nonbonding radius | half the shortest distance separating 2 nuclei during a collision between atoms
what is a bonding atomic radius?
half the distance between 2 bonded atoms
What is the periodic TREND for atomic size?
increases right –> left (opposite of Zeff) | increases down a group
What are ionic radii?
determined by the interatomic distances in ionic compounds
What are the 3 things ionic size depends on?
nuclear charge | #electrons | orbitals in which electrons are in
What is the size of cations compared to their parent atom?
SMALLER than parent atom
What is the size of anions compared to their parent atom?
LARGER than parent atom (more electrons = increase repulsion = bigger e- cloud)
What is the isoelectric series?
ions have the same number of electrons
What are the 5 ions that all have 10 electrons?
O2- | F- | Na+ | Mg2+ | Al3+
What is ionizing energy?
minimum energy required to remove an electron of a gaseous atom/ion from ground state
What is the first ionization energy?
to remove the 1st electron
What is the second ionization energy?
to remove the 2nd electron
What is the relationship between removing an electron and the ionization energy?
higher ionization energy = more difficult to remove electron
What is the periodic TREND for the 1st ionization energy (I1)?
increases left –>right | increases up a group | s/p > d > f
What are the 3 factors that affect ionization energy?
atomic size (smaller = higher I) | Zeff | avg. nucleus -electron distance
What are the 2 situations when the trend for ionization energy doesn’t apply?
when the added valence e- in the next element: enters a new higher energy state | is first e- pair in one box (orbital) of a sublevel (degenerate orbitals)
What is the electron configuration for cations?
lost from the highest energy level (n)
What is the electron configuration for anions?
filled up to ns2 np6
What is electron affinity?
energy change accompanying the electron addition to a gas atom
What is the difference between ionization energy and electron affinity?
both measure energy change: | IE = when atom LOSES an electron ; EA = when atom GAINS an electron
What is the general period TREND for electron affinity?
increases left –> right
What are the 3 exceptions to the periodic trend for electron affinity?
Group 2A = s-orbital full = X- unstable = decrease EA | Group 8A = p-orbital full = X- unstable = decrease EA | Group 5A = p-orbital partially full = can add e- = slight decrease EA
What are the 7 properties of metals?
abundant in nature | form cations | shiny luster | conduct heat/electricity | malleable/ductile | solids @RT (not Hg) | low IE
What are the 2 properties of metals in chemical reactions?
metal oxides = basic | metal+nonmetal = ionic compound
What are the 6 properties of nonmetals?
Right side of table | form anions | dull/brittle solids | can be in any form (g, l, s) | large negative electronegativity | poor conductors
What are the 2 properties of nonmentals in chemical reactions?
nonmetal oxides = acidic | nonmetal+nonmetal = molecular compound
What are metalloids?
have a mix characteristics of some metal and nonmetal properties
What is a characteristic of metalloids?
electrical semi-conductors
What are the 6 metalloids?
B, Si, Ge, As, Sb, Te
What is the Group 1A metals called?
alkali metals
What are the 6 characteristics/properties of alkali metals?
soft/metallic solids | only found as compounds in nature | metallic properties | LOW melting points/densities | low IE | exothermic when react with H2O
What are the Group 2A metals called?
alkaline earth metals
What are the 3 characteristics of alkaline earth metals?
higher melting points/densities than Group 1A | slightly higher IE than Group 1A | increase reactivity down the group
What is the periodic TREND for Group 6A?
increase metallic character down the group
What is the periodic TREND for Group 7A
high EA all around
What is Group 7A called? What is its characteristic?
halogens | reacts readily with metals = halides
What is Group 8A called? What are its 4 characteristics?
noble gases | highest EA | unreactive | found as monoatomic gases | LARGE IE
