Question 1

According to VSEPR theory, what is the electron domain geometry and bond angle for a molecule with three electron groups around the central atom?

Accepted Answer

Trigonal planar, $$120\degree$$

Question 2

Which of the following molecules is expected to have a bent molecular geometry due to the presence of lone pairs?

Accepted Answer

H$$_2O$$

Question 3

What is the predicted bond angle in ammonia (NH$$_3) $$and why is it less than the ideal tetrahedral angle?

Accepted Answer

$$107\degree$$; lone pairs cause greater repulsion than bonding pairs

Question 4

For a molecule with five electron groups, such as PCl$$_5$$, what is the electron domain geometry and the bond angles?

Accepted Answer

Trigonal bipyramidal; $$90\degree$$ and $$120\degree$$

Question 5

Which statement best describes how double and triple bonds are counted in VSEPR theory?

Accepted Answer

Each double or triple bond counts as a single electron group

Question 6

Methanol (CH$$_3OH) $$has two centers: carbon and oxygen. What are the molecular geometries around each center?

Accepted Answer

Carbon: tetrahedral; Oxygen: bent

Question 7

Which molecule is nonpolar due to the vector sum of its bond dipoles being zero?

Accepted Answer

CO$$_2$$

Question 8

In VSEPR theory, where should lone pairs be placed in a trigonal bipyramidal geometry to minimize repulsion?

Accepted Answer

Equatorial positions

Question 9

Which of the following best explains why lone pairs affect bond angles more than bonding pairs?

Accepted Answer

Lone pairs occupy more space and exert greater repulsion

Question 10

What is the molecular geometry and bond angle for SF$$_6$$?

Accepted Answer

Octahedral; $$90\degree$$

Question 11

Which of the following molecules will have a molecular dipole moment?

Accepted Answer

H$$_2O$$

Question 12

A molecule has four electron groups: two bonds and two lone pairs. What is its molecular geometry?

Accepted Answer

Bent

Question 13

Which of the following is the correct order of repulsion strength from largest to smallest?

Accepted Answer

Lone pair \u003e triple bond \u003e double bond \u003e single bond

Question 14

What is the effect of lone pairs on the geometry of water (H$$_2O$$)?

Accepted Answer

They reduce the bond angle to less than $$109.5\degree$$

Question 15

Which notation is used to represent the 3D structure of a molecule in a 2D drawing?

Accepted Answer

Line-dash-wedge notation

Question 16

If a molecule has six electron groups around the central atom, what is its electron domain geometry?

Accepted Answer

Octahedral

Question 17

Which of the following molecules is expected to be polar due to its molecular geometry?

Accepted Answer

SO$$_2$$

Question 18

What is the molecular geometry of NO$$_2^- ($$nitrite ion)?

Accepted Answer

Bent

Question 19

Which step is NOT part of the strategy for determining VSEPR structures for larger molecules?

Accepted Answer

Ignore lone pairs on central atoms

Question 20

Which of the following best describes a bond dipole moment?

Accepted Answer

A vector representing the separation of charge in a covalent bond

Covalent Bonding II: Molecular Shapes, VSEPR Theory, and Advanced Bonding Models

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