Question 1

Which of the following best explains why oil spills on the ocean surface spread out into thin layers rather than forming droplets?

Accepted Answer

Oil molecules are nonpolar and have weak intermolecular forces with water, causing them to spread out.

Question 2

Which statement about the relationship between bond length and bond energy is correct?

Accepted Answer

Shorter bonds generally have higher bond energies.

Question 3

What is the main factor that determines the geometry of a molecule according to VSEPR theory?

Accepted Answer

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

Question 4

Which of the following molecules has a trigonal planar geometry?

Accepted Answer

BF$_3$

Question 5

Given the Lewis structure for water (H$_2$O), what is the molecular geometry and approximate bond angle?

Accepted Answer

Bent, 104.5$^	ext{o}$

Question 6

Which of the following best describes the difference between ionic and covalent bonding?

Accepted Answer

Ionic bonding involves transferring electrons, while covalent bonding involves sharing electrons.

Question 7

What is the formal charge on the central nitrogen atom in the Lewis structure of the nitrate ion (NO$_3^-$)?

Accepted Answer

$0$

Question 8

Which molecule will have the largest dipole moment?

Accepted Answer

H$_2$O

Question 9

Which of the following statements about electronegativity is correct?

Accepted Answer

Electronegativity decreases down a group and increases across a period.

Question 10

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

Accepted Answer

$1.33$

Question 11

Which of the following best explains why the bond angle in ammonia (NH$_3$) is less than the ideal tetrahedral angle?

Accepted Answer

The lone pair on nitrogen exerts greater repulsion than bonding pairs, compressing the bond angle.

Question 12

Which of the following molecules is expected to be nonpolar?

Accepted Answer

CO$_2$

Question 13

What is the correct Lewis structure for the phosphate ion (PO$_4^{3-}$)?

Accepted Answer

Phosphorus with four single bonds to oxygen, each oxygen with three lone pairs, and three negative charges distributed on three oxygens.

Question 14

Which of the following factors does NOT affect the lattice energy of an ionic compound?

Accepted Answer

The temperature at which the compound is formed.

Question 15

Which of the following molecules has an octahedral geometry?

Accepted Answer

SF$_6$

Question 16

What is the main reason for the difference in bond length between a C-H bond and a C-Cl bond?

Accepted Answer

Chlorine is larger than hydrogen, so the C-Cl bond is longer.

Question 17

Which of the following ions has resonance structures?

Accepted Answer

NO$_3^-$

Question 18

Which of the following molecules will have a trigonal bipyramidal geometry?

Accepted Answer

PCl$_5$

Question 19

What is the formal charge on the oxygen atom in the Lewis structure of water (H$_2$O)?

Accepted Answer

$0$

Question 20

Which of the following statements about dipole moments is correct?

Accepted Answer

A molecule with a symmetrical geometry may have no net dipole moment even if it has polar bonds.

Chemical Bonding and Molecular Structure: Study Notes part 1

Study Guide - Practice Questions