Chapter 6 - Ionic and Molecular Compounds

This set of flashcards covers key terminology and concepts from Chapter 6 on ionic and molecular compounds, emphasizing definitions and principles necessary for understanding chemical bonding and molecular geometry.

Ionic bond

A chemical bond formed through the transfer of electrons from a metal to a nonmetal, resulting in the formation of positively and negatively charged ions.

Covalent bond

A chemical bond formed when two nonmetal atoms share valence electrons to achieve a stable electron configuration.

Valence electrons

Electrons in the outermost shell of an atom that are involved in forming bonds.

Octet rule

The principle that atoms tend to bond in such a way that they each have eight electrons in their valence shell.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Anion

A negatively charged ion formed when an atom gains one or more electrons.

Polyatomic ion

A group of atoms that collectively have a charge and behave as a single unit in chemical reactions.

Lewis structure

A diagram that represents the valence electrons of atoms within a molecule, showing the bonding between atoms and lone pairs.

Electronegativity

The ability of an atom to attract shared electrons in a chemical bond.

Dipole-dipole interaction

A type of intermolecular force that occurs between polar molecules, where positive and negative ends attract each other.

Hydrogen bond

A strong intermolecular force that occurs when hydrogen is bonded to highly electronegative elements like fluorine, oxygen, or nitrogen.

Dispersion forces

Weak intermolecular forces arising from temporary dipoles in nonpolar molecules.

VSEPR theory

Valence Shell Electron-Pair Repulsion theory, which predicts the geometry of molecules based on repulsion between electron pairs.

Tetrahedral shape

A molecular geometry where a central atom is bonded to four other atoms, arranged in a tetrahedron with bond angles of approximately 109°.

Linear shape

A molecular geometry where two atoms are bonded to a central atom in a straight line, resulting in a bond angle of 180°.

Trigonal planar shape

A molecular geometry where three atoms are bonded to a central atom, forming a flat triangle with bond angles of 120°.

Bent shape

A molecular geometry where two atoms are bonded to a central atom, but the presence of lone pairs causes the angle to be less than 120°.

Electronegativity difference (∆EN)

A measure used to predict bond type: covalent bonds (0-0.4), polar covalent bonds (0.5-1.8), and ionic bonds (greater than 1.8).

Properties of ionic compounds

Typically have high melting points and are solid at room temperature due to strong attractions between oppositely charged ions.

Lewis dot structure for H2

A representation showing how two hydrogen atoms share electrons to achieve a stable configuration.

Diatomic molecules

Molecules that consist of two atoms, such as H2, N2, O2, F2, Cl2, Br2, and I2.