Chapter 8- Chemical Bonding Flashcards
Ionic
Metals and nonmetals
Unfair sharing of electrons
Covalent
Nonmetals and nonmetals
Fair sharing of electrons
Can be polar or nonpolar
Metallic
E cloud bonds atoms
Octet rule
Atoms tend to lose or gain until they are surrounded by 8 electrons except H which needs two
Polar bonds
Covalent bonds in which electrons are shared unequally die to the differences in the elements electronegativities
Polar molecule (dipole)
A molecule containing a polar bond which results in an uneven distribution of electrons
Dipole moment
Measurement of the magnitude of dipole
Reasonable structures
Molecules with more than one plausible structure
Lattice energy (Eel)
Energy required to completely separate 1 mol of an ionic crystal into its gaseous ions
All ionic compounds
Are solid and exist as a crystal lattice
Ionic bonds are ______ than covalent bonds
Stronger
Formula for lattice energy
Eel = (constant times charges of ions) / distance between nuclei
Lattice energy
All about charge and attraction
Formal charge
The charge that an atom in a molecule would have if all of its bonding electron pairs were shared equally between atoms
(Allows us to predict correct form of a molecule)
Formal charge adds up to
The charge of the ion
Halogens only form
Single bonds
Anything form the throw period down can
Hybridize
Heat of reaction
Bonds broken-bonds formed
VSEPR
Valance shell electron pair repulsion theory
Electron pairs on a central atom
Bonded or unbounded will repel, thus creating the molecules shape
Electron domains
The areas where the electrons are likely to be located
Electron domain geometry
Shape created by the electron domains
Molecular geometry
The shape created by the arrangement of atoms
Shape of two electron domains
Linear (180 degrees)
Shape of three electron domains
Trigonal planar (120) Bent(120) (one unbounded pair)
Shape of four electron domains
Tetra hedral (109) Trigonal pyramidal (107) Bent (two unbounded electrons) (104)
Tetrahedral
109
Trigonal pyramidal
107
Bent (one unbounded electron pair)
120
Bent (two unbounded electron pairs)
104
Trifocals planar
120
How does a bond affect a molecules polarity
A polar bond “bond dipole” is a vector quantity. Therefore it has magnitude and direction
Bonding site
Orbital with only one electron in it
Valance bond theory
Covalent bonds are formed by overlapping atomic orbitals which contain electrons
Does orbital overlap happen in polyatomic molecules?
Yes but the atomic orbitals (s,p,d) mix to form a hybrid orbital
Linear
Sp
Trifocals planar
Sp2
Tetrahedral
Sp3
Covalent bonds can be classified as
Sigma or pi bonds
Sigma bond
End to end overlap of atomic orbitals
The electron density of sigma bonds
Is concentrated along a line that connects the nuclei
Pi bond
A side by side overlap of Unhybridized atomic orbitals
Electron density of pi bonds
Is concentrated above and below a line that connects the nuclei
Single bond
Sigma bond
Double bond
One sigma
One pi
Triple bond
One sigma
Two pis
Electronic geometry may be different from molecular geometry because
The electronic geometry refers to how the electrons are arranged, but the molecular geometry indicates the net shows of the molcule
VSEPR theory is based on
Minimization of repulsion among valance electron pairs
The central atom in compounds with square planar geometric always abet the octet rule
True
Large electronegativities difference affects molecular properties
By making boss stronger and shorter
Makes bonds highly polar
Makes molecule highly polar if molecular geometry permits
Metallic bond
Metals and metals
Electron clouds around atom
