Q: Given a bond with a dipole moment $$\mu = 3.0\ D$$ and a bond length $$r = 1.0\ \text{\AA}$$, what is the magnitude of the charge separation $$q$$? (1 D = $$3.336 \times 10$$^{-30}$$ C·m, 1$$\ \text{\AA} = 1.0 \times $$10^{-10} m)$$

$$q = 1.0 \times 10$$^{-19}$$\ \text{C}$$

Question 1

Which of the following is the correct electronic configuration for nitrogen (atomic number 7)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^3$$

Question 2

Which of the following molecules violates the octet rule?

Accepted Answer

BF$$_3$$

Question 3

Given a compound with 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass, and a molar mass of 60 g/mol, what is its molecular formula?

Accepted Answer

C$$_2H$_4O$_2$$

Question 4

Which of the following is the correct Lewis structure for the nitrate ion (NO$$_3^-$$)?

Accepted Answer

Three resonance structures, each with one N=O double bond and two N–O single bonds, with a negative charge delocalized on the oxygens.

Question 5

A solution is prepared by dissolving 3.65 g of HCl (molar mass = 36.5 g/mol) in enough water to make 1.00 L of solution. What is the pH of the solution?

Accepted Answer

$$pH = 1.0$$

Question 6

Which of the following best describes the difference between a sigma ($$\sigma) $$and a pi ($$\pi) $$bond in terms of wavefunction overlap?

Accepted Answer

A $$\sigma$$ bond results from head-on overlap of orbitals, while a $$\pi$$ bond results from side-by-side overlap.

Question 7

Which of the following compounds would you expect to have the highest boiling point?

Accepted Answer

CH$$_3CH$_2CH$_2OH$$

Question 8

Which of the following statements about resonance structures is correct?

Accepted Answer

Resonance structures differ only in the placement of electrons, not atoms.

Question 9

Which of the following is a correct application of the Arrhenius definition of acids and bases?

Accepted Answer

An acid increases $$[H^+] in $$aqueous solution, a base increases $$[OH^-].$$

Question 10

Which of the following factors will increase the acidity of a molecule?

Accepted Answer

Increasing the electronegativity of atoms near the acidic hydrogen (inductive effect).

Question 11

Which of the following best explains why acetic acid (CH$$_3$$COOH) is more acidic than ethanol (CH$$_3CH$_2OH$$)?

Accepted Answer

The conjugate base of acetic acid is stabilized by resonance.

Question 12

Which of the following molecules can form hydrogen bonds with water?

Accepted Answer

CH$$_3NH$_2$$

Question 13

Given a bond with a dipole moment $$\mu = 3.0\ D$$ and a bond length $$r = 1.0\ 	ext{\AA}$$, what is the magnitude of the charge separation $$q$$? (1 D = $$3.336 	imes 10$$^{-30}$$ C·m, 1$$\ 	ext{\AA} = 1.0 	imes $$10^{-10} m)$$

Accepted Answer

$$q = 1.0 	imes 10$$^{-19}$$\ 	ext{C}$$

Question 14

Which of the following is the correct formal charge on the central atom in the Lewis structure of SO$$_4$$^{2-}$$?

Accepted Answer

Formal charge on S is 0.

Question 15

Which of the following best describes the effect of hybridization on acidity?

Accepted Answer

Hydrogens attached to $$sp-$$hybridized carbons are more acidic than those attached to $$sp^2 or$$ $$sp^3$$ carbons.

Question 16

Which of the following compounds is most soluble in water?

Accepted Answer

NaCl

Question 17

Which of the following is a correct statement about London dispersion forces?

Accepted Answer

They are present in all molecules, but are the only intermolecular force in nonpolar molecules.

Question 18

Which of the following is the correct Bronsted-Lowry definition of a base?

Accepted Answer

A base is a proton acceptor.

Question 19

Rank the following compounds in order of increasing boiling point: CH$$_4$$, CH$$_3Cl$$, CH$$_3OH.$$

Accepted Answer

CH$$_4$$ \u003c CH$$_3Cl$$ \u003c CH$$_3OH$$

Question 20

Which of the following is a correct Lewis definition of an acid?

Accepted Answer

An acid is an electron pair acceptor.

Organic Chemistry Exam I Study Guide: Structure, Bonding, Acids & Bases

Guida di studio - Domande di pratica

Study guide - Flashcard