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Flashcards in Concepts of Matter II Deck (23):

Hund's Rule

Electrons tend to occupy degenerate (orbitals that have the same energy) orbitals singly and in the same direction


Pauli's Exclusive Principle

states that no two electrons in an atom could have the same set of 4 quantum numbers (the 4th which is the spin quantum number must be different)


Quantum Numbers

n = principle quantum level (1 to infinity)
script L = azimuthal quantum number (0 to 1-n) tells us the shape of the orbital
m subscript x = magnetic quantum number ( -script L to script L) describes the orientation in space
m subscript s = spin quantum number (-1/2 to 1/2)


Describe the creation of the periodic table

Dimitri Mendeleev was credited with the development of the periodic table
It was then arranged in terms of increasing atomic weight
The modern periodic table is arranged by increasing atomic number by Henry Moseley


Describe how the periodic table is arranged

elements fall into rows called periods and columns called groups or families
There A (main groups) and B (transition metals) groups, 8 A groups and 10 B groups
Arrangement goes from metals -> metalloids -> non metals


Relate the electron configuration to the periodic table

highest quantum level containing electron corresponds to the period of the element
total number of electrons in the highest quantum level corresponds to the group of the element


Name physical properties

atomic radius
ionization energy
electron affinity


Explain the atomic radius

Refers to the size of the atom
decreases across the periods, increases down the groups
decreases across because the number of quantum level remain the same, this results in a greater net force. the net force increases and pulls to valence electrons closer to the nucleus, thus decreasing the radius
increases down occurs because of the added quantum level


Explain Zeff

Zeff is the net force penetrating to the valence electrons (effective nuclear charge)
it increases across the periods and decreases down the groups


Describe Ionization energy

This is the amount of energy required to remove an electron(s) from the valence shell of a gaseous atom
increases across the period and decreases down the groups
increases across the periods because as the Zeff gets larger, the harder it is to remove electrons.
Vice versa for decreasing down the groups


Describe electron affinity

the is the energy change that occurs when an electron(s) are added to the valence shell of a gaseous atom
increases across the periods (more exothermic) and it decreases down the groups (less exothermic)


Explain exo and endothermic

Exothermic- energy being released
Endothermic- energy being absorbed
(It's exothermic if electrons are being added to the same energy level and endothermic if added to a higher energy level)


Describe electronegative

this is the ability of an atom to attract shared electrons to itself
increases across the period and decreases down the groups


Describe and list types of chemical bond

any force that holds atoms together
-ionic bonding
-covalent bonding
-metallic bonding
-hydrogen bonding


Describe Ionic bonding

type of bonding that involves transfer if electrons, occurs b/w a metal (forms a + cation) and a non metal (form an - anion)
When in solutions or moistened, these compounds will conduct electricity because they break up into corresponding ion
Smallest unit is a formula unit
also called electro valence bonding


Describe a latice network

when ions come together to form the crystals, they position themselves at maximum angles and distance to minimize attraction and repulsion, this results in a latice network and energy being released called latice energy
latice energy is a function of ionic radius and ionic charge
grater charge = grater latice energy
smaller radius = greater latice energy


Compare size of an atom to its ion

cation is smaller than its atom
size of anion is greater than its atom
cation have more energy than their atom
anions have less energy than their atom


what are isoelectronic species

when ions have the same electron config. as the closest noble gas


Describe the 2 types of ionic compounds

Binary ionic compounds- 2 elements held together by ionic bonding
Ternary ionic compounds- contain 3 or more elements (must have a polyatomic ion) This compound contains ionic and covalent bonding


name and describe the systems used to reflect the valence in the naming of a compound with more than one valence

Traditional (Latin) System
Has the concept of '-ic' and '-ous'
'-ic' is the higher valence & '-ous' for the lower one

Stock System
Uses roman numerals to identify the charge of an ion


Describe Covalent bonding

type of bonding that involves sharing of electrons
occurs between 2 non-metals
are called molecular compounds and the smallest unit is a molecule
ARE NON ELECTRO LIGHTS (because they do not form ions)


Describe the VSEPR

Valence Shell Electron Pair Repulsion Theory
Theory that suggest that the atoms position themselves at maximum angles and distances to minimize repulsion by valence electrons.
When this happens it results in a particular shape of a molecule


Describe Electron pair geometry

Based on the total amount of electron pairs (bonding and non bonding around the atom)
Bonding pair is an electron pair b/w 2 atoms while a non bonding pair is an electron pair by itself around the central atom
[for this theory, double and triple bonds are considered one electron pair]