Chapter 7 - Multi-electron Species and Periodic Properties

Question 1

effective nuclear charge

Answer 1

nuclear charge that the valence electron(s) “feel”

Question 2

shielding

Answer 2

decreased electrostatic attraction between nucleus and outermost electrons because of other electron shells

Question 3

spin quantum number

Answer 3

-allowed values of +1/2 and -1/2
-spin up is +
-spin down is -

Question 4

Aufbau principle

Answer 4

electrons will occupy orbitals with the lowest available energy levels before occupying orbitals with higher energy levels

Question 5

Pauli exclusion principle

Answer 5

-no two electrons in an atom or ion may have the same four quantum numbers
-never violated, even in an excited state

Question 6

Hund’s rule

Answer 6

when orbitals that have the same energy are available, electrons occupy them singly with the same spin before being paired within an orbital

Question 7

paramagnetic

Answer 7

-species with one or more unpaired electrons
-possess an overall magnetic moment

Question 8

dimagnetic

Answer 8

-species with no unpaired electrons
-do not possess overall magnetic moment

Question 9

covalent radius

Answer 9

estimate for radius which is applied to single-bonded homonuclear species

Question 10

ionic radius

Answer 10

estimate made from the crystal lattice structure

Question 11

van der Waal radius

Answer 11

uses distances between non-bonded atoms to estimate the boundary of an atom

Question 12

atomic radius trend

Answer 12

as you go down a group, n increases therefore atomic radius increases

Question 13

ionic radius of cations

Answer 13

-smaller than corresponding neutral atoms
-because cations experience less electron-electron repulsion

Question 14

ionic radius of anions

Answer 14

-larger than corresponding neutral atoms
-because anions experience greater electronic repulsion

Question 15

ionic radius of isoelectronic ions

Answer 15

decrease with increasing Z

Question 16

ionization energy

Answer 16

-minimum energy required to remove a single electron from an atom, molecule, or ion in its gaseous state

Question 17

ionization energy trend

Answer 17

-increases from left to right across the periodic table
-decrease top to bottom within a particular group of the periodic table

Question 18

electron affinity

Answer 18

energy change that results from the addition of a single electron to an atom or ion in its gaseous state

Question 19

electron affinity trend

Answer 19

-increases across the period table only to the halogens
-decreases going down a group