Question 1

The molecular geometry of the BeCl₂ molecule is ________,and this molecule is ________. A)bent, nonpolar B)linear, polar C)bent, polar D)seesaw, polar E)linear, nonpolar

Accepted Answer

The molecular geometry of BeCl₂ (BeCl2) is linear because beryllium forms two single bonds with two chlorine atoms and has no lone pairs, leading to a 180-degree bond angle. This molecule is nonpolar because the electronegativity difference between Be and Cl is not enough to create a significant dipole moment, and the linear geometry allows the dipole moments to cancel out.

Question 2

The hybrid orbital set used by the central atom in ClO₂^- is ________. A)sp B)sp² C)sp³ D)sp³d E)sp³d²

Accepted Answer

The hybridization of the central atom in ClOSB12SBSBP-SBP is determined using the formula:
Hybridization = (number of sigma bonds + number of lone pairs) around the central atom
In this case, the central atom (which is S) is bonded to 2 other atoms (Cl and O) and has 2 lone pairs. So the total number of sigma bonds and lone pairs around the central atom is 4, which corresponds to sp3 hybridization. However, since one of the lone pairs in S is involved in bonding with the adjacent P atom, it forms a double bond with the P atom, resulting in a trigonal planar arrangement of atoms around the S atom. This means that the hybrid orbitals used by the S atom are sp2 hybrids, which contain one unhybridized p orbital. The answer choice that corresponds to this hybrid orbital set is C, which contains 3 sp hybrid orbitals and 2 unhybridized p orbitals.

Question 3

The hybrid orbital set used by the central atom in PCl₅ is ________. A)sp B)sp² C)sp³ D)sp³d E)sp³d²

Accepted Answer

PCl5 has a trigonal bipyramidal shape, which requires the central phosphorus atom to use sp3d hybridization to accommodate five bonding pairs.

Question 4

How many hybrid orbitals are formed upon the mixing of three atomic orbitals?
A)three
B)six
C)four
D)one
E)five

Accepted Answer

When three atomic orbitals mix, they form three hybrid orbitals. This is based on the principle that the number of hybrid orbitals formed is equal to the number of atomic orbitals that combine.

Question 5

How many hybridized s atomic orbital(s)are found in an sp²-hybridized carbon atom? A)0 B)3 C)2 D)1 E)4

Accepted Answer

An sp^3 hybridized carbon atom has one s orbital and three p orbitals that hybridize to form four sp^3 hybrid orbitals. Therefore, there is one hybridized s atomic orbital.

Question 6

A typical triple bond consists of ________ sigma bond(s)and ________ pi bond(s).
A)1, 2
B)2, 2
C)1, 3
D)0, 3
E)1, 4

Accepted Answer

A triple bond consists of one sigma bond and two pi bonds. The sigma bond is formed by end-to-end overlapping and pi bonds are formed by lateral overlapping of atomic orbitals.

Question 7

Of the molecules below,only ________ is polar. A)CO₂ B)CH₄ C)PF₅ D)SnF₃ E)H₂

Accepted Answer

SnF₃ is polar because it has an asymmetrical shape and an uneven distribution of electron density, leading to a net dipole moment. The other molecules are nonpolar due to their symmetrical shapes and even distribution of electron density.

Question 8

The bond angles in a tetrahedral molecule are ________ degrees.
A)109.5
B)120
C)90
D)45
E)<45

Accepted Answer

A tetrahedral molecule has four electron groups around the central atom, which results in a bond angle of approximately 109.5 degrees due to the electron repulsion between these groups.

Question 9

How many unhybridized p atomic orbital(s)are found in an sp-hybridized carbon atom?
A)4
B)2
C)0
D)1
E)3

Accepted Answer

The answer of How many unhybridized p atomic orbital(s)are found...

Question 10

Using the VSEPR model,the molecular geometry of the central atom in IF₅ is ________. A)tetrahedral B)square planar C)square pyramidal D)seesaw E)trigonal bipyramidal

Accepted Answer

The molecular formula IF₅ seems to be a typographical error. However, assuming the molecule in question is IF5, which fits the context of the question, the central atom (Iodine) is surrounded by 5 bonding pairs of electrons and no lone pairs, leading to a square pyramidal geometry according to the VSEPR model.

Question 11

Which of the following molecules would be considered nonpolar? A)PF₃ B)Br₂S C)BeH₂ D)TeCl₂ E)HCl

Accepted Answer

BeH₂ is nonpolar because it has a linear geometry, and the dipole moments cancel each other out, resulting in no net dipole moment.

Question 12

Construct a molecular orbital diagram for a Li₂ molecule.According to molecular orbital theory,the σ_1s orbital is ________ and the σ_1s^* orbital is ________. A)filled, filled B)half-filled, filled C)empty, filled D)filled, empty E)filled, half-filled

Accepted Answer

The σ1s orbital is filled because both lithium (Li) and sulfur (S) have two electrons to contribute to this bonding orbital, making it fully occupied. The σ1s* (sigma 1s star) orbital, which is the antibonding counterpart, is also filled due to the presence of additional electrons from both atoms that occupy the antibonding orbital after the bonding orbitals are filled.

Question 13

According to valence bond theory,which orbitals overlap in the formation of the bond in Cl₂? A)4p on Cl and 4p on Cl B)3p on Cl and 3p on Cl C)sp on Cl and sp on Cl D)3s on Cl and 3s on Cl E)2p on Cl and 2p on Cl

Accepted Answer

Valence bond theory suggests that the bond formation in Cl2 involves the overlap of the outermost p orbitals of each chlorine atom. Since chlorine is in the third period of the periodic table, it uses its 3p orbitals for bonding.

Question 14

According to valence bond theory,which orbitals overlap in the formation of the bond in  ?
A)3s
B)3p
C)4s
D)4p
E)3d

Accepted Answer

The answer of According to valence bond theory,which orbitals overlap...

Question 15

The electron-domain geometry of a boron-centered compound BH₃ is trigonal planar.The hybridization of the central boron atom is ________. A)sp² B)sp³d² C)sp³ D)sp³d E)sp

Accepted Answer

The electron-domain geometry being trigonal planar indicates that the central boron atom is involved in three sigma bonds and has no lone pairs, which corresponds to sp^2 hybridization.

Question 16

The hybrid orbital set used by the central atom in SO₃ is ________. A)sp B)sp² C)sp³ D)sp³d E)sp³d²

Accepted Answer

In SO₃, the central sulfur atom forms three sigma bonds with oxygen atoms and has no lone pairs, resulting in a trigonal planar geometry. This geometry corresponds to sp² hybridization.

Question 17

According to valence bond theory,which orbitals overlap in the formation of the bond in HCl?
A)1s on H and 2p on Cl
B)2s on H and 3p on Cl
C)1s on H and 3s on Cl
D)1s on H and 3p on Cl
E)1s on H and 4p on Cl

Accepted Answer

In HCl molecule, hydrogen has only 1s orbital and chlorine has 3p orbital. Therefore, according to valence bond theory, the sigma bond is formed by the overlap of the 1s orbital of hydrogen and the 3p orbital of chlorine. Thus, the correct option is D) 1s on H and 3p on Cl.

Question 18

The molecular geometry of the IF₅ molecule is ________,and this molecule is ________. A)trigonal bipyramidal, polar B)trigonal bipyramidal, nonpolar C)trigonal planar, polar D)square pyramidal, polar E)square pyramidal, nonpolar

Accepted Answer

The molecular geometry of IF5 is square pyramidal due to the presence of five bonding pairs and one lone pair on the central iodine atom. This geometry leads to an asymmetric distribution of electron density, making the molecule polar.

Question 19

Of the following,only ________ has sp² hybridization of the central atom. A)NF₃ B)HCN C)BF₃ D)ICl₃ E)CH₄

Accepted Answer

The hybridization of BF₃ is sp², which is the only option listed with this specific hybridization. The other options have different hybridizations.

Question 20

Mixing one s atomic orbital and one p atomic orbital gives rise to ________. A)three sp² hybrid orbitals B)two sp² hybrid orbitals C)two sp³ hybrid orbitals D)three sp hybrid orbitals E)two sp hybrid orbitals

Accepted Answer

Mixing one s and one p orbital gives rise to two hybrid orbitals called sp hybrid orbitals.

Quiz 9: Molecular Geometry and Bonding Theories

The molecular geometry of the BeCl₂ molecule is ,and this molecule is .

The hybrid orbital set used by the central atom in ClO₂^- is ________.

The hybrid orbital set used by the central atom in PCl₅ is ________.

How many hybrid orbitals are formed upon the mixing of three atomic orbitals?

How many hybridized s atomic orbital(s) are found in an sp²-hybridized carbon atom?

A typical triple bond consists of sigma bond(s) and pi bond(s) .

Of the molecules below,only ________ is polar.

The bond angles in a tetrahedral molecule are ________ degrees.

How many unhybridized p atomic orbital(s) are found in an sp-hybridized carbon atom?

Using the VSEPR model,the molecular geometry of the central atom in IF₅ is ________.

Which of the following molecules would be considered nonpolar?

Construct a molecular orbital diagram for a Li₂ molecule.According to molecular orbital theory,the σ_1s orbital is ________ and the σ_1s^* orbital is ________.

According to valence bond theory,which orbitals overlap in the formation of the bond in Cl₂?

According to valence bond theory,which orbitals overlap in the formation of the bond in ?

The electron-domain geometry of a boron-centered compound BH₃ is trigonal planar.The hybridization of the central boron atom is ________.

The hybrid orbital set used by the central atom in SO₃ is ________.

According to valence bond theory,which orbitals overlap in the formation of the bond in HCl?

The molecular geometry of the IF₅ molecule is ,and this molecule is .

Of the following,only ________ has sp² hybridization of the central atom.

Mixing one s atomic orbital and one p atomic orbital gives rise to ________.

Quiz 9: Molecular Geometry and Bonding Theories

The molecular geometry of the BeCl2 molecule is ________,and this molecule is ________.

The hybrid orbital set used by the central atom in ClO2- is ________.

The hybrid orbital set used by the central atom in PCl5 is ________.

How many hybrid orbitals are formed upon the mixing of three atomic orbitals?

How many hybridized s atomic orbital(s) are found in an sp2-hybridized carbon atom?

A typical triple bond consists of ________ sigma bond(s) and ________ pi bond(s) .