Introduction to Valence Bond Theory

What is the main difference between valence bond theory and Lewis theory?

• Valence bond theory uses quantum mechanics to describe electrons.

• Lewis theory uses quantum mechanics to describe electrons.

• Lewis theory considers electrons as waves.

• Valence bond theory treats electrons as dots.

What are atomic orbitals?

• Fixed points in space.

• Paths that electrons follow.

• Regions where electrons are likely to be found.

• Exact locations of electrons.

What are hybrid orbitals?

• Combinations of standard atomic orbitals.

• Fixed electron paths.

• Regions with no electrons.

• Standard atomic orbitals.

What happens to potential energy as two atoms approach each other?

• It decreases and then increases sharply.

• It increases indefinitely.

• It decreases to zero.

• It remains constant.

What is bond energy?

• The energy at equilibrium bond length.

• The energy required to break a bond.

• The energy when atoms are far apart.

• The energy at maximum potential energy.

How do two orbitals overlap to form a bond?

• By combining two full orbitals.

• By combining two half-filled orbitals.

• By combining a full and an empty orbital.

• By combining two empty orbitals.

What is the result of overlapping orbitals in terms of electron spins?

• Electrons stop spinning.

• Electrons have opposite spins.

• Electrons have the same spin.

• Electrons are removed.

What is the ground state electron configuration of hydrogen?

• 1s2

• 1s1

• 2s1

• 2p1

What is the expected bond angle in hydrogen sulfide according to valence bond theory?

• 180°

• 90°

• 120°

• 109.5°

Why is valence bond theory a better treatment for hydrogen sulfide than VSEPR theory?

• It predicts a larger bond angle.

• It predicts a bond angle closer to the actual value.

• It predicts a smaller bond angle.

• It predicts the exact bond angle.