CHEM 2261 Final Exam Vocabulary
Test Questions with Correct/Verified
Solutions 2025-2026 Updated.
Orbital - Answer region of space around the nucleus where electrons are formed
aufbau principle - Answer s orbital will be filled before the p orbitals in the same shell
Valence electrons - Answer electrons in the outermost shell responsible for all bonding
Octet rule - Answer States that atoms lose, gain or share electrons in order to acquire a full
set of eight valence electrons
Ionic bonds - Answer results from the transfer of electrons from one element to the other
Covalent bonds - Answer results from sharing electrons between 2 atoms
Formal charge - Answer is the charge assigned to individual atoms in a Lewis structure
Isomers - Answer different molecules with the same molecular formula
Constitutional isomers - Answer have the same formula but differ in connectivity
Bond length - Answer distance between the centers of 2 bonded atomic nuclei
Bond angles - Answer determines the shape around any atom surrounded by 2 or more
groups
Linear - Answer 2 groups, 180º bond angles
Trigonal planar - Answer 3 groups, 120º bond angles
Tetrahedral - Answer 4 groups, 109.5º bond angles
, Lewis structure - Answer A structural formula in which electrons are represented by dots;
dot pairs or dashes between two atomic symbols represent pairs in covalent bonds.
Condensed structure - Answer a molecular representation in which bonds are not specifically
shown but rather are understood by the order in which atoms are written
Skeletal (bond-line) structures - Answer Heteroatoms are joined directly to the carbons to
which they are bonded with no intervening hydrogens
Hybridization - Answer the mixing of several atomic orbitals to form the same total number
of equivalent hybrid orbitals
sp^3-hybridized orbitals - Answer 25% s, 75% p
tetrahedral geometry
109.5 bond angles
ex) Cs all single bonds
sp^2-hybridized orbitals - Answer 33% s, 67% p
trigonal planar geometry
120 bond angles
ex) Cs 1 double bond
sp hybridization - Answer 50% s, 50% ; shorter bc more s character
Electronegativity - Answer measure of an atom's affinity for or tendency to attract electrons;
inc. left to right and bottom to top
Nonpolar - Answer when electronegativity is the same between 2 atoms
Polar convalent - Answer unequal sharing between atoms
Dipole - Answer created by equal but opposite charges that are separated by a short
distance
Dipole moment - Answer an arrow indicates the direction of the dipole
Electrostatic potential maps - Answer show how electron density is distributed in a molecule
Test Questions with Correct/Verified
Solutions 2025-2026 Updated.
Orbital - Answer region of space around the nucleus where electrons are formed
aufbau principle - Answer s orbital will be filled before the p orbitals in the same shell
Valence electrons - Answer electrons in the outermost shell responsible for all bonding
Octet rule - Answer States that atoms lose, gain or share electrons in order to acquire a full
set of eight valence electrons
Ionic bonds - Answer results from the transfer of electrons from one element to the other
Covalent bonds - Answer results from sharing electrons between 2 atoms
Formal charge - Answer is the charge assigned to individual atoms in a Lewis structure
Isomers - Answer different molecules with the same molecular formula
Constitutional isomers - Answer have the same formula but differ in connectivity
Bond length - Answer distance between the centers of 2 bonded atomic nuclei
Bond angles - Answer determines the shape around any atom surrounded by 2 or more
groups
Linear - Answer 2 groups, 180º bond angles
Trigonal planar - Answer 3 groups, 120º bond angles
Tetrahedral - Answer 4 groups, 109.5º bond angles
, Lewis structure - Answer A structural formula in which electrons are represented by dots;
dot pairs or dashes between two atomic symbols represent pairs in covalent bonds.
Condensed structure - Answer a molecular representation in which bonds are not specifically
shown but rather are understood by the order in which atoms are written
Skeletal (bond-line) structures - Answer Heteroatoms are joined directly to the carbons to
which they are bonded with no intervening hydrogens
Hybridization - Answer the mixing of several atomic orbitals to form the same total number
of equivalent hybrid orbitals
sp^3-hybridized orbitals - Answer 25% s, 75% p
tetrahedral geometry
109.5 bond angles
ex) Cs all single bonds
sp^2-hybridized orbitals - Answer 33% s, 67% p
trigonal planar geometry
120 bond angles
ex) Cs 1 double bond
sp hybridization - Answer 50% s, 50% ; shorter bc more s character
Electronegativity - Answer measure of an atom's affinity for or tendency to attract electrons;
inc. left to right and bottom to top
Nonpolar - Answer when electronegativity is the same between 2 atoms
Polar convalent - Answer unequal sharing between atoms
Dipole - Answer created by equal but opposite charges that are separated by a short
distance
Dipole moment - Answer an arrow indicates the direction of the dipole
Electrostatic potential maps - Answer show how electron density is distributed in a molecule
