4.8Chemical Bonding and Molecular Geometry

These flashcards cover key concepts, definitions, and processes related to chemical bonding and molecular geometry, with a focus on ionic and covalent bond formation.

What is the octet rule in chemistry?

Atoms are most stable when they have eight electrons in their outermost shell.

What are ionic compounds?

Compounds composed of ions held together by ionic bonds, which are electrostatic forces of attraction between oppositely charged cations and anions.

How do metals and nonmetals behave in ionic bond formation?

Metals lose electrons easily (low ionization energy) while nonmetals gain electrons easily (high electron affinity).

What is the structure of sodium chloride (NaCl)?

NaCl does not represent individual molecules but rather the simplest ratio of ions in a three-dimensional lattice.

What do cations strive to achieve in terms of electronic structure?

Cations want to be isoelectronic with the noble gas of the previous row.

What do anions strive to achieve in terms of electronic structure?

Anions want to be isoelectronic with the noble gas of the same row.

What characterizes a polar covalent bond?

Unequal sharing of electrons between atoms in a covalent bond.

What is the relationship between potential energy and bond length in covalent bond formation?

Bond length represents the distance between two bonded atoms at their minimum potential energy.

What is released during the making of covalent bonds?

Energy is released; this process is exothermic.

What is required during the breaking of covalent bonds?

Energy is spent; this process is endothermic.

What determines whether a covalent bond is nonpolar or polar?

Electronegativity of the bonding atoms.

What is electronegativity?

A measure of the tendency of an atom to attract electrons or electron density toward itself.

What does a dipole moment represent in a polar bond?

It indicates the direction of polarity, pointing toward the more electronegative atom.

What bond type is formed with zero electronegativity difference?

Pure covalent bond.

What is the electronegativity value range that indicates a polar covalent bond?

Intermediate electronegativity difference between bonding atoms.

How is electron affinity defined?

The energy released when an atom gains an electron.

What is the unit for electronegativity?

It has no unit; it is a comparative value.