CHM 115 Chapter 11

Which of the following statements correctly describe sp^3 hybrid orbitals?

- An sp^3 orbital is unsymmetrical in shape, having one small and one large lobe. - The four sp^3 hybrid orbitals of a group are equivalent in shape and energy.

Why is the hybridization model necessary to explain the bonding in a molecule such as CH4?

- The atomic electron configuration of carbon cannot account for four equivalent bonds. - The observed bond angles cannot be explained with reference to atomic orbitals.

Which of the following statements correctly defines hybrid orbitals?

- orbitals used for bonding that are formed by "mixing" atomic orbitals from the same atom.

Why is rotation about a pi bond restricted?

Free rotation would disrupt the parallel arrangement of the p orbitals, causing the bond to break.

Sigma bond

is a single bond.

Pi bond

more than one bond (double bond, triple bond)

sp^3d^2

octahedral

The hybridization of one s and one p orbital will result in the formation of two ____ hybrid orbitals. This will leave _____ unhybridized valence p orbital(s), lying at right angles to the hybrid orbitals.

sp; two

sp^3

tetrahedral

which of the following statements correctly describes hybrid orbital?

the type of hybrid orbital varies depending on the specific combination of atomic orbitals the spatial orientations of the hybrid orbitals match observed molecular shapes the shape and orientation of a hybrid orbital allow maximum overlap with an orbital from another atom to form a bond

sp^3d

trigonal bipyramidal

sp^2

trigonal planar

A double bond is always made up of ___ sigma and ____ pi bond(s). A double bond is _____ than a sigma bond.

1, 1, stronger

valence bond theory proposes that before a covalent bond forms, atom orbitals from a given atom can combine to form new atomic orbitals. this process is called _____ of orbitals and the new atomic orbital are referred to as ____ orbitals

hybridization, hybrid

sp

linear

Hybrid orbitals are designated by using a superscript to indicate the _____ of each type of orbital used to form them. For example, the designation sp^2 indicates that _____ s and _____ p orbital(s) were combined to form this orbital type.

number; one; two

A group of sp^3 hybrid orbitals is formed by the hybridization of ______ s and ______ p orbital(s) from the valence shell of an atom. These hybrid orbitals have the same ____ and energy.

one; three; shape

A double bond acts as _____ electron group(s) even though there is/are ____ electron pair(s) shared between the bonding atoms. This is because each electron pair occupies a different orbital, which reduces _____ between them. Similarly the three bonds of a triple bond form _____ group(s).

one; two; repulsion; one

The boom atom in the structure shown requires 3 equivalent bonding orbitals, which are formed by combining ___ s and ____ p orbital(s) from the boron atom to form 3 equivalent ____ hybrid orbitals. There is/are _____ unhybridized p orbital(s) on the boron atom, which contain(s) no electrons.

one; two; sp2; one

Valence bond theory describes a single covalent bond as the _____ of orbitals from two atoms to form a shared space, which is occupied by _____ electron(s).

overlap, 2

A bond formed by sideways overlap of two p orbitals (one from each bonding atom) is called a(n) ______ bond. This type of bond has ____ regions of electron density.

pi, 2

determine the hybridization of the central atom by...

predicting the geometry of he molecule using VSEPR deduce the hybridization of the central atom based on the geometry of the molecule draw the lewis structure of the molecule

A bond formed by the overlap of two s orbitals or the end-to-end overlap of two orbitals that have p character is called a _____ bond. This bond has its highest electron density between the ____ of the two bonded atoms.

sigma; nuclei

Which of the following options correctly describe sp hybrid orbitals?

- The energy of an sp hybrid orbital lies between the energies of the original s and p orbital that were mixed. - Each sp hybrid orbital has one large and one small lobe.

Which of the following statements correctly describe hybrid orbitals?

- The spatial orientations of the hybrid orbitals match observed molecular shapes. - The type of hybrid orbital formed varies depending on the specific combination of atomic orbitals. - The shape and orientation of a hybrid orbital allows maximum overlap with an orbital from another atom to form a bond.

Which of the following statements correctly describe the formation of sp^2 hybrid orbitals?

- a group of sp^2 hybrid orbitals assumes a trigonal planar geometry. - the formation of sp^2 hybrid orbitals leaves one unhybridized valence p orbital.

Which of the following statements correctly describe a pi bond?

- a multiple bond always contains at least one pi bond. - a pi bond is formed by the side-to-side overlap of two p orbitals.

Which of the following statements correctly describe a sigma bond?

- single bonds are sigma bonds - a sigma bond results from end-to-end overall of two orbitals

A central atom can be surrounded by five or six electron groups if _____ orbitals are available for bonding. The appropriate number of equivalent bonding orbitals is formed by combining _____ s orbital(s), ____ p orbital(s), and one or two _____ orbitals.

d; one; three; d

A particular hybrid orbital is designated sp^3d^2. What information is provided by the superscripts in this designation?

The number of each type of atomic orbital combined to produce this type of hybrid orbital.

When should the VSEPR model and hybridization theory be applied to describe bonding?

Whenever an observed molecular shape needs to be rationalized in terms of atomic orbitals.

Hybrid orbitals are formed by the combination of "mixing" of ________ orbitals from a specific atom. The number of hybrid orbitals formed is ____ to/than the number of orbitals mixed, and the ______ of hybrid orbitals varies to the specific orbitals mixed.

atomic; equal; type

According to valence bond theory, a(n) ____ bond is formed by the overlap of orbitals from two atoms. In order to explain the observed bond angles in many species it is proposed that the atomic orbitals first form _____ orbitals, which differ from the orbitals of the isolated atoms.

covalent, hybrid