Download Chapter 1 Vocabulary

Chapter 1 Vocabulary
1. Antibonding MO – A molecular orbital that is higher in energy than
the atomic orbitals from which it is formed.
2. Atomic Mass – The average mass number of the atoms of an element.
3. Bond Angle – The angle formed between two adjacent bonds.
4. Bond Length – The equilibrium distance between the nuclei of two
atoms that are bonded to each other.
5. Bond Strength – An alternative name for bond dissociation energy.
6. Bonding MO – A molecular orbital that is lower in energy than the
atomic orbitals from which it is formed.
7. Covalent Bond – A bond formed by sharing electrons between atoms.
8. Ground-State Electron Configuration – The most stable, lowestenergy electron configuration of a molecule or atom.
9. Isotope – Atoms of the same element that have different mass
numbers.
10.Kekule Structure – A method of representing molecules in which a
line between atoms indicates a bond.
11.Lewis Structure – A representative of a molecule showing valence
electrons as dots.
12.Line-Bond Structure – A representation of a molecule showing
covalent bonds as lines between atoms.
13.Lone-Pair Electrons – Nonbonding valence-shell electron pairs. Lonepair electrons are used by nucleophiles in their reactions with
electrophiles.
14.Molecular Orbital (MO) Theory – A description of covalent bond
formation as resulting from a mathematical combination of atomic
orbitals (wave functions) to from molecular orbitals.
15.Molecule – A neutral collection of atoms held together by covalent
bonds.
16.Node – A surface of zero electron density within an orbital. For
example, a p orbital has a nodal plane passing through the center of
the nucleus, perpendicular to the axis of the orbital.
17.Nonbonding Electrons – Valence electrons that are not used in
forming covalent bonds.
18.Orbital – A wave function, which describes the volume of space
around a nucleus in which an electron is most likely to be found.
19.Organic Chemistry – The study of carbon compounds.
20.Pi Bond – The covalent bond formed by sideways overlap of atomic
orbitals. For example, carbon-carbon double bonds contain a pi bond
formed by sideways overlap of two p orbitals.
21.Shell (Electron) – A group of an atom’s electrons with the same
principal quantum number.
22.Sigma Bond – A covalent bond formed by head-on overlap of atomic
orbitals.
23.sp Hybrid Orbital – A hybrid orbital derived from the combination of
an s and a p atomic orbital. The two sp orbitals that result from
hybridization are oriented at an angle of 180 degrees to each other.
24.sp2 Hybrid Orbital – A hybrid orbital derived by combination of an s
atomic orbital with two p atomic plane at angles of 120 degrees to
each other.
25.sp3 Hybrid Orbital – A hybrid orbital derived by combination of an s
atomic orbital with three p atomic orbitals. The four sp3 hybrid
orbitals that result are directed toward the corners of a regular
tetrahedron at angles of 109 degrees to each other.
26.Valence Bond Theory – A bonding theory that describes a covalent
bond as resulting from the overlap of two atomic orbitals.
27.Valence Shell – The outermost electron shell of an atom.