AP Chemistry Unit 2 Practice Flashcards

A complete set of flashcards covering AP Chemistry Unit 2 topics including chemical bonding, VSEPR theory, molecular geometries, and hybridization.

What is a Chemical Bond?

An attractive force that holds atoms together.

What type of bond is formed by the electrostatic attraction between oppositely charged ions?

Ionic Bond

What is a Covalent Bond?

Bond formed when atoms share electron pairs.

How is a Polar Covalent Bond defined?

A covalent bond with unequal sharing of electrons.

What is a Nonpolar Covalent Bond?

A covalent bond with equal or nearly equal sharing of electrons.

What type of bond involves the attraction between metal cations and delocalized electrons?

Metallic Bond

What is a Valence Electron?

An electron in the outermost energy level involved in bonding.

What is the Octet Rule?

Atoms tend to gain, lose, or share electrons to achieve eight valence electrons.

What is a Lewis Structure?

A diagram showing valence electrons and bonding.

In a molecule, which atom is the Central Atom?

The atom around which other atoms are arranged.

What is a Terminal Atom?

An atom bonded to only one other atom.

What is the difference between Single, Double, and Triple Bonds?

A Single Bond involves one shared pair of electrons, a Double Bond involves two shared pairs, and a Triple Bond involves three shared pairs.

What is Resonance?

Two or more valid Lewis structures for the same molecule.

What is an Expanded Octet?

More than eight electrons around a central atom.

What is an Incomplete Octet?

Fewer than eight electrons around a central atom.

How is Formal Charge defined?

The hypothetical charge assigned to an atom in a Lewis structure.

What is a Coordinate Covalent Bond?

A covalent bond in which one atom provides both bonding electrons.

What term refers to the distance between the nuclei of two bonded atoms?

Bond Length

What is Bond Energy?

The energy required to break one mole of a specific bond.

What is Bond Strength?

The amount of energy needed to break a bond.

What does Bond Order refer to?

The number of shared electron pairs between two atoms.

What is Electronegativity?

An atom's ability to attract bonding electrons.

What is Bond Polarity?

The unequal distribution of electron density in a bond.

How is a Dipole defined?

A separation of partial positive and partial negative charges.

What is a Dipole Moment?

A measure of bond or molecular polarity.

What is represented by the symbol $\delta$ in bonding?

Partial Positive Charge ($\delta$) or Partial Negative Charge ($\delta$), representing a slight charge on an atom.

What is VSEPR Theory?

A model predicting molecular shape based on electron pair repulsion.

What is an Electron Domain?

A region of electron density around a central atom.

Compare Electron Geometry and Molecular Geometry.

Electron Geometry is the arrangement of all electron domains around the central atom, while Molecular Geometry is the three-dimensional arrangement of atoms in a molecule.

What is a Bonding Pair vs. a Lone Pair?

A Bonding Pair is shared in a covalent bond, while a Lone Pair is a pair of valence electrons not involved in bonding.

What is a Bond Angle?

The angle between adjacent bonds.

What is the bond angle for a Linear molecular shape?

$$180^\circ$$

Describe the Trigonal Planar geometry.

Three electron groups arranged $120^\circ$ apart.

What is the bond angle for Tetrahedral geometry?

$$109.5^\circ$$

Describe Trigonal Pyramidal geometry.

A pyramidal shape with one lone pair on the central atom.

How many electron groups surround a central atom in Trigonal Bipyramidal geometry?

Five electron groups.

What molecular shape is derived from trigonal bipyramidal geometry and has one lone pair?

Seesaw

What are the characteristics of a T-Shaped molecule?

A molecular shape with three bonded atoms and two lone pairs.

What is Octahedral geometry?

Six electron groups around a central atom.

Describe the Square Pyramidal shape.

Five bonded atoms and one lone pair around a central atom.

Describe the Square Planar shape.

Four bonded atoms in one plane with two lone pairs.

What is Molecular Polarity?

The overall distribution of charge in a molecule.

What is a Net Dipole?

The vector sum of all bond dipoles.

How do bond dipoles behave in a Symmetrical Molecule?

The bond dipoles cancel out.

How do bond dipoles behave in an Asymmetrical Molecule?

The bond dipoles do not cancel.

What is the difference between a Polar Molecule and a Nonpolar Molecule?

A Polar Molecule has a net dipole moment, while a Nonpolar Molecule has no net dipole moment.

Define Hybridization.

The mixing of atomic orbitals to form hybrid orbitals.

Describe $sp$ Hybridization.

Hybridization producing two electron domains.

Describe $sp^2$ Hybridization.

Hybridization producing three electron domains.

Describe $sp^3$ Hybridization.

Hybridization producing four electron domains.

What is a Sigma Bond ($\sigma$ Bond)?

The first covalent bond formed by end-to-end orbital overlap.

What is a Pi Bond ($\pi$ Bond)?

A bond formed by the sideways overlap of p orbitals.