Question 1

Which of the following best describes the Lewis model of chemical bonding?

Accepted Answer

Atoms transfer or share electrons to attain stable electron configurations.

Question 2

What is the correct Lewis structure for a phosphorus atom?

Accepted Answer

A 'P' symbol surrounded by five dots, each representing a valence electron.

Question 3

Which of the following compounds is formed by the transfer of electrons from a metal to a nonmetal, resulting in an ionic bond?

Accepted Answer

KCl

Question 4

How many valence electrons are present in an oxygen atom, and how is this represented in its Lewis structure?

Accepted Answer

6 valence electrons, represented as six dots around the 'O' symbol.

Question 5

Which of the following molecules contains a double bond in its Lewis structure?

Accepted Answer

O2

Question 6

What is the correct sequence of steps for drawing a Lewis structure for a covalent compound?

Accepted Answer

Write the skeletal structure, count valence electrons, distribute electrons to give octets, form double/triple bonds if needed.

Question 7

Which of the following is an exception to the octet rule?

Accepted Answer

BF3, where boron has only 6 electrons around it.

Question 8

Which of the following best explains why water (H2O) is a polar molecule?

Accepted Answer

Water has polar O-H bonds and a bent molecular geometry, so the dipole moments do not cancel.

Question 9

What is the molecular geometry of ammonia (NH3) according to VSEPR theory?

Accepted Answer

Trigonal pyramidal

Question 10

Which of the following statements about resonance structures is correct?

Accepted Answer

Resonance structures are two or more valid Lewis structures for the same molecule, and the true structure is an average of them.

Question 11

Which of the following best describes the difference between a polar covalent bond and a pure covalent bond?

Accepted Answer

A polar covalent bond has an unequal sharing of electrons due to a difference in electronegativity.

Question 12

Which of the following molecules is nonpolar, despite having polar bonds?

Accepted Answer

CO2

Question 13

A molecule has four electron groups around the central atom, two of which are lone pairs. What is the molecular geometry?

Accepted Answer

Bent

Question 14

Which of the following best explains why oil and water do not mix?

Accepted Answer

Water is polar and oil is nonpolar, so they repel each other.

Question 15

Which of the following is the correct Lewis structure for the cyanide ion (CN⁻)?

Accepted Answer

A triple bond between C and N, with a lone pair on each atom, enclosed in brackets with a negative charge.

Question 16

Which of the following statements about artificial sweeteners is supported by molecular shape theory?

Accepted Answer

Artificial sweeteners taste sweet because their molecular shape allows them to fit into taste receptor sites.

Question 17

Which of the following best describes the effect of lone pairs on molecular geometry?

Accepted Answer

Lone pairs repel bonding pairs, reducing bond angles and altering the molecular geometry.

Question 18

A molecule has three electron groups around the central atom, all of which are bonding pairs. What is the electron geometry and bond angle?

Accepted Answer

Trigonal planar, 120°

Question 19

Which of the following best explains why soap can remove grease from your hands?

Accepted Answer

Soap molecules have a polar head that interacts with water and a nonpolar tail that interacts with grease.

Question 20

Which of the following is true about the relationship between electronegativity difference and bond type?

Accepted Answer

A large electronegativity difference (greater than 2.0) results in an ionic bond.

Chapter 10: Chemical Bonding – Study Notes

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