Chapter 1 - Structure And Bonding Flashcards
Aufbau Principle
Lowest-energy orbitals fill up first.
Note that the 4s orbital lies between the 3p and 3d orbitals.
1s2 2s2 2p5
( F ) Flourine
Atoms with the same atomic number but different mass numbers are called
ISOTOPES
According to the quantum mechanical model, the behavior of a specific electron in an atom can be described by a mathematical expression called a
Wave Function
The orbitals in an atom are organized into different ________________, centered around the nucleus and having successively larger size and energy.
Electron shells
Hund’s rule
If two or more empty orbitals of equal energy are available, one electron occupies each with spins parallel until all orbitals are half-full
How many electrons does each of the following elements have in its outer- most electron shell? Magnesium? Sulfur?
Magnesium - 2
Sulfur - 6
Electrons act in some ways as if they were spinning around an axis. This spin can have two orientations, denoted as up and down. Only two electrons can occupy an orbital, and they must be of opposite spin, a statement called the
Pauli Exclusion Principle
1s2 2s2 2p6 3s2 3p3
( P ) Phosphorus
According to _________________, a covalent bond forms when two atoms approach each other closely and a singly occupied orbital on one atom overlaps a singly occupied orbital on the other atom.
Valence Bond Theory
2s orbital combines with only two of the three available 2p orbitals results to
Three sp2 hybrid orbitals
Mnemonic #1 - Electron configuration
Aufbau, pa order ako. Exclude mo si Pauli and use your hund’s.
Two models have been developed to describe covalent bonding.
Valence bond theory and molecular orbital theory
An answer was provided in 1931 by ________, who showed mathematically how an s orbital and three p orbitals on an atom can combine, or hybridize, to form four equivalent atomic orbitals with tetrahedral orientation
Linus Pauling
Define valence shell.
Atom’s outermost shell.
Differentiate ionic and covalent bonds.
Ionic bonding is simply defined as donation of electrons between atoms while covalent bonds share electrons.
First proposed in 1916 by G. N. Lewis, where carbon bonds to other atoms, not by gaining or losing electrons, but by sharing them.
Covalent bond.
Difference between kekule and lewis structure.
Kekule structures: Line-bond structures
Lewis structures: Electron-dot structures
Making bonds always ________ energy, and breaking bonds always ______ energy.
Releases, Absorbs
He discovered in 1828 that it was possible to convert the “inorganic” salt ammonium cyanate into the “organic” substance urea, which had previously been found in human urine.
Friedrich Wöhler
Define organic chemistry.
Organic chemistry, then, is the study of carbon compounds.
Valence electrons that are not used for bonding.
Lone-pair electrons/nonbonding electrons
Formed by head-on overlaps of atomic orbitals slong a line drawn between nuclei.
Sigma Bonds
Pi bond
Interaction between unhybridized p orbitals
