Question 1

Which hybridization scheme best explains the geometry and bond angles observed in methane (CH$$_4$$)?

Accepted Answer

$$sp^3$$ hybridization; bond angles of 109.5^\circ$

Question 2

Which of the following statements about the electron configuration of carbon in methane is correct?

Accepted Answer

The carbon atom uses $$sp^3$$ hybrid orbitals, each forming a $$\sigma$$ bond with hydrogen.

Question 3

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

Angular momentum quantum number ($$\ell)$$

Question 4

What is the formal charge on the central carbon atom in the Lewis structure of methane (CH$$_4$$)?

Accepted Answer

0

Question 5

Which of the following molecules has a net dipole moment of zero?

Accepted Answer

Carbon dioxide ($$CO_2)$$

Question 6

Which of the following best describes the difference between $$\sigma$$ and $$\pi$$ bonds?

Accepted Answer

$$\sigma$$ bonds are stronger and formed by end-to-end overlap; $$\pi$$ bonds are weaker and formed by sideways overlap.

Question 7

Which of the following elements can form an expanded octet in its compounds?

Accepted Answer

Sulfur

Question 8

A molecule has three electron groups around its central atom. What is the expected hybridization and bond angle?

Accepted Answer

$$sp^2$$ hybridization; 120^\circ$

Question 9

Which of the following is a correct statement about resonance structures?

Accepted Answer

Resonance structures differ only in the placement of $$\pi$$ electrons and lone pairs.

Question 10

Which of the following best explains why hybrid orbitals are used to describe bonding in methane rather than pure atomic orbitals?

Accepted Answer

Hybrid orbitals allow for the formation of identical bonds with the correct geometry observed in methane.

Question 11

Which of the following ions has a formal charge of $$-1 on $$the oxygen atom?

Accepted Answer

Hydroxide ion ($$OH^-)$$

Question 12

Which of the following best describes the electron configuration of the ground state of carbon?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^2$$

Question 13

Which of the following molecules contains delocalized electrons due to resonance?

Accepted Answer

Carbonate ion ($$CO_3$$^{2-}$$)

Question 14

Which of the following is true regarding the bond length and bond strength in carbon-hydrogen bonds as the hybridization changes from $$sp^3 to$$ $$sp$$?

Accepted Answer

Bond length decreases and bond strength increases from $$sp^3 to$$ $$sp.$$

Question 15

Which of the following best describes the difference between localized and delocalized electrons in resonance structures?

Accepted Answer

Localized electrons are shared between two atoms; delocalized electrons are spread over three or more atoms.

Question 16

Which of the following is the correct order of increasing electronegativity for the elements: C, N, O, F?

Accepted Answer

C \u003c N \u003c O \u003c F

Question 17

Which of the following best describes the effect of resonance on the stability of a molecule?

Accepted Answer

Resonance lowers the energy and increases the stability of a molecule.

Question 18

Which of the following is a valid Lewis structure for the methyl anion ($$CH_3$$^-$$)?

Accepted Answer

Carbon with three bonds and one lone pair

Question 19

Which of the following best explains why the bond angle in water ($$H_2O) is $$less than the ideal tetrahedral angle?

Accepted Answer

The presence of two lone pairs on oxygen increases electron pair repulsion, reducing the bond angle.

Chapter 1: Electronic Structure and Bonding in Organic Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard