$\#\text{ of valence electrons} - (\#\text{ of bonds}) - (\#\text{ of nonbonding electrons})$

Question 1

Which of the following best describes a polar covalent bond?

Accepted Answer

A bond in which two atoms share electrons unequally, resulting in a partial charge separation.

Question 2

Which molecule is nonpolar despite containing polar bonds?

Accepted Answer

CO$_2$

Question 3

What is the formal charge on the central atom in the Lewis structure of NH$_4^+$?

Accepted Answer

$0$

Question 4

Which of the following statements about bond order is correct?

Accepted Answer

Bond order increases as the number of shared electron pairs increases.

Question 5

Given the Lewis structure for ozone (O$_3$), which concept explains the equal bond lengths observed experimentally?

Accepted Answer

Resonance

Question 6

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

Accepted Answer

CH$_4$

Question 7

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

Accepted Answer

Bent

Question 8

Which of the following best explains why the O-H bond in water is polar?

Accepted Answer

Oxygen is more electronegative than hydrogen, causing unequal sharing of electrons.

Question 9

What is the bond order of the carbon-oxygen bonds in CO$_3^{2-}$ (carbonate ion)?

Accepted Answer

$1.33$

Question 10

Which statement about lone pairs and bond angles in tetrahedral molecules is correct?

Accepted Answer

Lone pairs decrease the bond angle between atoms.

Question 11

Which molecule is expected to have a net dipole moment?

Accepted Answer

CH$_2$Cl$_2$

Question 12

What is the electron geometry of SF$_4$?

Accepted Answer

Trigonal bipyramidal

Question 13

Which of the following is the correct formula for calculating formal charge?

Accepted Answer

$\#	ext{ of valence electrons} - (\#	ext{ of bonds}) - (\#	ext{ of nonbonding electrons})$

Question 14

Which molecule has a trigonal planar molecular geometry?

Accepted Answer

BF$_3$

Question 15

Which of the following best describes resonance stabilization?

Accepted Answer

The stability of a molecule due to the delocalization of its electrons across multiple structures.

Question 16

Which of the following molecules is polar due to its molecular geometry, even though all bonds are identical?

Accepted Answer

NH$_3$

Question 17

A molecule has six electron domains around the central atom. What is its electron geometry?

Accepted Answer

Octahedral

Question 18

Which of the following statements about the octet rule is correct?

Accepted Answer

Hydrogen does not follow the octet rule and is stable with two electrons.

Question 19

Which of the following best describes a dipole moment?

Accepted Answer

A vector representing the polarity of a bond due to separation of charge.

Question 20

Which molecule is expected to have the smallest bond angle?

Accepted Answer

H$_2$O

Chemical Bonding I: Covalent Bonds, Lewis Structures, VSEPR, and Molecular Polarity

Study Guide - Practice Questions