Chem Ch.8 Review

True of False: A shared pair of electrons is represented by a double dash.

False

True or False: A molecular formula shows the arrangement of the atoms in a molecule.

False

True or False: Electrons fill the antibonding molecular orbital first to produce a stable covalent bond.

False

True or False? All diatomic molecules contain double bonds

False

The actual bonding in ozone is a ________ of the extremes represented by its _________.

Hybrid, resonance structures

The strongest of the intermolecular forces are ___________.

Hydrogen bonds

What is a coordinate covalent bond?

It is a covalent bond in which one atom contributes both bonding electrons.

What are the common molecular shapes?

Linear triatomic, Pyramidal, Bent triatomic, Trigonal planar, Tetrahedral, and Trigonal bipyramidal

What are two properties of molecular compounds?

Low melting and boiling points(below 300º C), exist as gases or liquids at room temperature.

Compounds that are formed when two or more atoms combine to form molecules are called ________.

Molecular compounds

What is the arrangement of atoms within a molecule called?

Molecular structure

Most elements found in nature, with the exception of the _______, exist as molecules.

Noble gases

How are electrons shared in each type of bond: Nonpolar bond________ Polar bond_______

Nonpolar bond- equally Polar bond- unequally

What is orbital hybridization?

Orbital hybridization occurs when several atomic orbitals mix to form the same total of equivalent hybrid orbitals.

The type of covalent bond that can be formed when p atomic orbitals overlap.

Pi and Sigma

How does electron sharing occur in forming covalent bonds?

Sharing of electrons usually occurs so that atoms acquire the electron configurations of noble gases.

When two s orbitals combine, the molecular orbital formed is called a(n) ________ bond.

Sigma

When the central atom of a molecule has unshared electrons, the bond angles will be ________ than when all the central atom's electrons are shared.

Smaller

What are resonance structures?

The are structures that occur when it is possible to write two or more valid electron dot formulas that have the same number of electron pairs for a molecule or ion.

What determines the physical properties of a compound?

The physical properties depend on the type of bonding in the compound.

What is VSEPR theory?

The valence-shell electron-pair repulsion theory states that because electron pairs repel, molecular shape adjusts so the valence-electron pairs are as far apart as possible.

Why does NO2 not follow the octet rule?

There is an unpaired electron present in both possible resonance structures.

True or False: Covalent bonds differ in the way electrons are shared by the bonded atoms, depending on the kind and number of atoms joined together.

True

True or False: Dispersion forces generally increase in strength as the number of electrons in a molecule increases.

True

True or False: Molecules with high bond dissociation energies are relatively unreactive.

True

True or False: Orbital hybridization theory can describe both the shape and bonding of molecules.

True

What is a molecular orbital?

When two atoms combine, their atomic orbitals overlap to produce orbitals that apply to the entire molecule.

What causes dispersion?

Dispersion forces are caused by the motion of electrons.

A chemical bond formed when atoms share two pairs of electrons is called a(n)

Double covalent bond

How many covalent bonds are in the nitrogen molecule?

3

What is a covalent bond?

A covalent bond is a bond formed when two atoms share electrons.

What is a molecular formula?

A molecular formula shows the types and numbers of atoms present in a molecule of a compound.

What is a molecule?

A molecule is a neutral group of atoms joined together by covalent bonds.

Structural formulas show the arrangement of ________ in molecules.

Atoms

What is bond dissociation energy?

Bond dissociation energy is the energy required to break the bond between two covalently bonded atoms.

Why do the chlorine atom in hydrogen chloride acquire a slightly negative charge?

Chlorine has a higher electronegativity than hydrogen, and, therefore, attracts the bonding electrons slightly away from hydrogen.