Question 1

Which statement best describes the main advantage of VSEPR theory over Lewis structures when predicting molecular properties?

Accepted Answer

VSEPR theory shows the 3D structure and can deduce the molecule’s overall dipole moment.

Question 2

How many electron groups are around the central atom in $$	ext{PH}_3$$?

Accepted Answer

4

Question 3

Which of the following molecules has a bond angle closest to $$109.5^	ext{o}$$?

Accepted Answer

$$	ext{CH}_4$$

Question 4

In VSEPR theory, why do lone pairs cause greater distortion in bond angles compared to bonding pairs?

Accepted Answer

Lone pairs are more repulsive due to their higher electron density.

Question 5

For a molecule with trigonal bipyramidal electron group geometry, where should lone pairs be placed first according to VSEPR theory?

Accepted Answer

Equatorial positions

Question 6

Which of the following molecules is non-polar despite having polar bonds?

Accepted Answer

$$	ext{CO}_2$$

Question 7

A carbon atom in ethyne ($$	ext{C}_2	ext{H}_2) is $$best described as having which geometry and hybridization?

Accepted Answer

Linear, $$sp$$

Question 8

Which of the following is a structural isomer of propanol ($$	ext{C}_3	ext{H}_8	ext{O}$$)?

Accepted Answer

Isopropanol

Question 9

Which statement about optical isomers is correct?

Accepted Answer

They are non-superimposable mirror images called enantiomers.

Question 10

What is the bond order of $$	ext{O}_2$$ according to Molecular Orbital Theory?

Accepted Answer

$$2$$

Question 11

Which molecule is paramagnetic according to its molecular orbital diagram?

Accepted Answer

$$	ext{O}_2$$

Question 12

In Valence Bond Theory, what type of bond is formed by the end-to-end overlap of atomic orbitals?

Accepted Answer

Sigma ($$	ext{\sigma}) $$bond

Question 13

Which hybridization is present in the central atom of $$	ext{BF}_3$$?

Accepted Answer

$$sp^2$$

Question 14

Which of the following statements about resonance and Valence Bond Theory is correct?

Accepted Answer

VBT can describe delocalized electrons without the need for resonance structures.

Question 15

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

Accepted Answer

$$	ext{NH}_3$$

Question 16

A molecule has 5 electron groups and 2 lone pairs on the central atom. What is its molecular geometry?

Accepted Answer

T-shaped

Question 17

Which of the following best explains why rotation around a double bond is restricted?

Accepted Answer

Pi bonds have electron density above and below the internuclear axis, preventing rotation.

Question 18

What is the molecular geometry and bond angle around the oxygen atom in water ($$	ext{H}_2	ext{O}$$)?

Accepted Answer

Bent, $$104.5^	ext{o}$$

Question 19

Which of the following is true about the bond order calculated from Molecular Orbital Theory for $$	ext{He}_2$$?

Accepted Answer

Bond order is $$0$$, so $$	ext{He}_2$$ does not exist under normal conditions.

Question 20

Which of the following molecules contains a chiral center?

Accepted Answer

$$	ext{CHBrClF}$$

Chemical Bonding II: VSEPR, Valence Bond Theory, and Molecular Orbital Theory

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