Question 1

Which of the following molecules has a trigonal planar molecular geometry according to the VSEPR model?

Accepted Answer

BF\_3

Question 2

What is the predicted bond angle in a molecule with a tetrahedral electron-domain geometry?

Accepted Answer

$$109.5^\circ$$

Question 3

Which statement best explains why the bond angle in water ($$H_2O) is $$less than the ideal tetrahedral angle?

Accepted Answer

Nonbonding electron pairs are physically larger and exert greater repulsion, compressing the bond angle.

Question 4

Which of the following molecules is nonpolar despite having polar bonds?

Accepted Answer

CO\_2

Question 5

A molecule has five electron domains around its central atom: three bonding pairs and two lone pairs. What is its molecular geometry?

Accepted Answer

T-shaped

Question 6

Which hybridization is associated with a central atom that has three electron domains?

Accepted Answer

$$sp^2$$

Question 7

Which of the following best describes a sigma ($$\sigma) $$bond?

Accepted Answer

Formed by head-to-head overlap with cylindrical symmetry along the internuclear axis

Question 8

What is the bond order of $$O_2$$ according to molecular orbital theory?

Accepted Answer

$$2$$

Question 9

Which molecule is predicted to be paramagnetic based on its molecular orbital diagram?

Accepted Answer

$$O_2$$

Question 10

Which of the following elements can form molecules with expanded valence shells?

Accepted Answer

Phosphorus (P)

Question 11

In the molecule $$SF_4$$, what is the electron-domain geometry and the molecular geometry?

Accepted Answer

Electron-domain: trigonal bipyramidal; Molecular: seesaw

Question 12

Which of the following statements about hybrid orbitals is correct?

Accepted Answer

Hybrid orbitals are formed by mixing atomic orbitals to create new orbitals of equal energy.

Question 13

Which molecule has a square planar molecular geometry?

Accepted Answer

$$XeF_4$$

Question 14

What is the main difference between localized and delocalized electrons in molecules?

Accepted Answer

Localized electrons are specifically shared between two atoms; delocalized electrons are shared by multiple atoms.

Question 15

Which of the following molecules has a bond angle greater than $$109.5^\circ$$ due to the presence of multiple bonds?

Accepted Answer

$$COCl_2$$

Question 16

What is the bond order for $$He_2$$ according to molecular orbital theory, and what does this imply?

Accepted Answer

Bond order = 0; $$He_2$$ does not exist as a stable molecule.

Question 17

Which of the following best describes the arrangement of electron domains in an octahedral geometry?

Accepted Answer

Six domains arranged at $$90^\circ$$ angles to each other

Question 18

Which step is NOT part of the VSEPR procedure for determining molecular geometry?

Accepted Answer

Specify the hybrid orbitals needed for bonding

Question 19

Which of the following molecules is expected to have $$sp^3$$ hybridization at its central atom?

Accepted Answer

$$NH_3$$

Question 20

In molecular orbital theory, what is the main feature of an antibonding orbital?

Accepted Answer

It contains a nodal plane where electron density is zero.

Chapter 9: Molecular Geometry and Bonding Theories – Study Notes

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