Chapter 7 Flashcards
What is effective nuclear charge?
the attractive force between electron and the nucleus
What does effective nuclear charge depend on?
depends on the magnitude of the nuclear charge and on the average distance between the nucleus and the electron
What happens to the force as the nuclear charge increases?
increases
What happens to the distance as nuclear charge increases?
moves farther from the nucleus
What do electrons in many electron atoms do to each other?
screened from the nucleus by the other electrons
What is the net attraction like for an atom that has more electrons than protons?
the net attraction is samller than it would experience in the absence of other electrons
IS effective nuclear charge greater or smaller than nuclear charge?
smaller
How do you find effective nuclear charge?
Zeff=Z-S
What happens to effective nuclear charge as l increases?
increases
What is the trend for effective nuclear charge?
increases left to right across a period
Why does effective nuclear charge increase across the period?
number of protons increase which causing the energy to increase which means the screening off the electrons are inefftive
What happens to effective nuclear charge going down a column?
effective nuclear charge icnreases slightly
Why does effective nuclear charge increases as we go down a group?
the more diffuse core electron cloud is less table to screen the valence electron from the nuclear charge
What is atomic radius?
an estimate of the size of an atom
What is bonding atomic radius
the radius of an atom by the distances separating it from other atoms to which it is chemically bonded
How do you find bonding atomic radius?
atomic radius x 1/2
What does bonding atomic radii do as you go across a period?
decrease
What does bonding atomic radii do as you go down a group?
increases
Why does the bonding atomic radii increase as you go down a group?
increase in the quantum number(n) of the outher electrons. the probablitly of being farther from the nucleus
Why does the bonding atomic radius tend to decrease across a period?
increase in Zeff across a period. draws the valence electrons closer to the nucleus
How do you determine ionic radii?
interatomic distances in ionic compounds
What does ionic radii depend on?
nuclear charge, the number of electrons, and the orbitals which the valence electrons reside
Are cations smaller or larger then there parent electrons?
smaller
Why are cations smaller then there parent atoms?
the number of electron-electron repulsions is reduced
Are anions bigger or smaller then there parent atoms?
bigger
Why are anions bigger then there parent atoms?
electrons are added to an atom, causing increased electron-electron repuslions
What does ionic radius do as you go down a group?
increases
What is an isoelectronic series?
a series of atoms, ions or molecules having the same number of electrons
What does ionic radius d as nuclear charge increases?
decreases
What is ionization energy?
the minimum enery required to remove an electron from the ground state of an isolated gaseous atom or ion
What is electron Affinity?
the energy change that occurs when an electron is added to a gaseous atom or ion
does ionization from a cation or an anion?
cation
When ionization occurs does it jump to another energy level or does it drop another energy level?
jump to antoher energy level
As ionization increases is it easier or harder to remove an electron?
harder
As ionization increases does the energy increase or decrease?
increase
What does the first ionization energy do as you go across a period?
increases
What does ionization energy do as you go down a group?
decreases
What does ionizaition energy measure?
when an atom loses an electron
What does electron affinity measure?
the energy change when an atom gains an electron
What causes electron affinity to increase(become more negative)
the greater the attraction between an atom and an added electron
What part of the periodic table has the most negative electron affinities?
noble gases
What part of the perioidc table is the most positive electron affinity?
halogens
What does electron affinity do as you go across a period?
increases(become more negative)
What does electron affinity do as you go down a group?
generally increases(become more negative
