Question 1

According to VSEPR theory, what is the primary factor that determines the shape of a molecule?

Accepted Answer

The arrangement of electron pairs (bonding and lone pairs) around the central atom

Question 2

What is the molecular geometry of $$\mathrm{CO_2$}$$ according to VSEPR theory?

Accepted Answer

Linear

Question 3

How does adding a lone pair to the central atom affect the bond angles in a molecule?

Accepted Answer

It decreases the bond angles

Question 4

Which of the following molecules has a trigonal pyramidal geometry?

Accepted Answer

$$\mathrm{NH_3$}$$

Question 5

A molecule has three bonding pairs and one lone pair on the central atom. What is its molecular geometry?

Accepted Answer

Trigonal pyramidal

Question 6

Which of the following best explains why the bond angle in $$\mathrm{H_2O} is $$much smaller than in $$\mathrm{SO_2$}$$, even though both have similar shapes?

Accepted Answer

Water has more lone pairs on the central atom, causing greater repulsion and a smaller bond angle.

Question 7

What is the bond angle in a molecule with a tetrahedral geometry?

Accepted Answer

$$109.5^\circ$$

Question 8

Which molecule below has a bent geometry due to the presence of two lone pairs on the central atom?

Accepted Answer

$$\mathrm{H_2O}$$

Question 9

If a molecule has two bonding pairs and no lone pairs on the central atom, what is its molecular geometry and bond angle?

Accepted Answer

Linear, $$180^\circ$$

Question 10

Which of the following statements about lone pairs and molecular shape is correct?

Accepted Answer

Lone pairs occupy more space than bonding pairs, causing bond angles to decrease.

Question 11

A molecule of $$\mathrm{SO_2$}$$ has how many total valence electrons?

Accepted Answer

18

Question 12

Which of the following best describes the effect of adding more atoms to the central atom on bond angles?

Accepted Answer

Bond angles adjust to minimize electron pair repulsion, which may increase or decrease depending on geometry.

Question 13

Given the Lewis structure for $$\mathrm{CH_4$}$$, what is the molecular geometry and the number of total valence electrons?

Accepted Answer

Tetrahedral, 8 valence electrons

Question 14

Which of the following molecules is planar and has a bond angle of $$120^\circ$$?

Accepted Answer

$$\mathrm{BF_3$}$$

Question 15

A molecule has four electron pairs (including both bonding and lone pairs) around the central atom. Which geometry does VSEPR theory predict?

Accepted Answer

Tetrahedral

Question 16

Which of the following best explains why $$\mathrm{CO_2$} is $$linear while $$\mathrm{H_2O} is $$bent?

Accepted Answer

$$\mathrm{CO_2$}$$ has no lone pairs on the central atom, while $$\mathrm{H_2O}$$ has two lone pairs.

Question 17

Which of the following molecules would you expect to have the smallest bond angle?

Accepted Answer

$$\mathrm{H_2O}$$

Question 18

If a molecule has two bonding pairs and two lone pairs on the central atom, what is its molecular geometry?

Accepted Answer

Bent

Question 19

Which of the following is a real-world application of VSEPR theory?

Accepted Answer

Predicting the shape of drug molecules to understand how they interact with biological targets

Question 20

A molecule has three bonding pairs and no lone pairs on the central atom. What is its geometry and bond angle?

Accepted Answer

Trigonal planar, $$120^\circ$$

VSEPR Theory and Molecular Geometry: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard