Question 1

Which of the following molecules contains a polar covalent bond and has a net molecular dipole moment?

Accepted Answer

Chloroform ($$\mathrm{$$CHCl_3$$})$$

Question 2

Given the following Lewis structure for formaldehyde ($$\mathrm{CH_2O}$$), what is the formal charge on the oxygen atom?

Accepted Answer

$$0$$

Question 3

Which of the following correctly describes the hybridization and geometry of the central carbon atom in acetylene ($$\mathrm{C_2H_2}$$)?

Accepted Answer

sp hybridized, linear

Question 4

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

Accepted Answer

Methanol ($$\mathrm{CH_3OH})$$

Question 5

Which of the following is a secondary alcohol?

Accepted Answer

2-Propanol ($$\mathrm{CH_3CHOHCH_3})$$

Question 6

Which of the following pairs are constitutional isomers?

Accepted Answer

1-Butene and 2-Butene

Question 7

Which of the following statements about Newman projections is correct?

Accepted Answer

The eclipsed conformation of ethane has maximum torsional strain.

Question 8

A cyclohexane ring with a single tert-butyl group will favor which conformation and why?

Accepted Answer

Equatorial, to minimize 1,3-diaxial interactions

Question 9

Which of the following best describes a meso compound?

Accepted Answer

A compound with chiral centers and a plane of symmetry, making it achiral

Question 10

How many stereoisomers are possible for 2,3-dibromobutane?

Accepted Answer

4

Question 11

Which of the following statements about enantiomers is correct?

Accepted Answer

They have identical physical properties except for their interaction with plane-polarized light.

Question 12

Which of the following is the correct IUPAC name for the compound with the structure $$\mathrm{CH_3CH_2CH_2Br}$$?

Accepted Answer

1-Bromopropane

Question 13

Which of the following functional groups is present in acetone?

Accepted Answer

Ketone

Question 14

Which of the following compounds would be expected to have the highest boiling point?

Accepted Answer

1-Propanol ($$\mathrm{CH_3CH_2CH_2OH})$$

Question 15

Which of the following best describes the acid-base reaction between acetic acid ($$\mathrm{CH_3COOH}$$, $$pK_a = 4.8) $$and ammonia ($$\mathrm{NH_3$}$$, $$pK_a = 9.2$$ for $$\mathrm{NH_4$^+}$$)?

Accepted Answer

The equilibrium favors the formation of acetate ion and ammonium ion.

Question 16

Given the $$pK_a$$ values: $$pK_a ($$ethanol) = 16, $$pK_a ($$acetic acid) = 4.8, which is the stronger acid and why?

Accepted Answer

Acetic acid, because it has a lower $$pK_a$$ value

Question 17

Which of the following best explains why the C–F bond in fluoromethane ($$\mathrm{CH_3F}) is $$more polar than the C–Cl bond in chloromethane ($$\mathrm{CH_3Cl}$$)?

Accepted Answer

Fluorine is more electronegative than chlorine.

Question 18

Which of the following best describes the relationship between cis-2-butene and trans-2-butene?

Accepted Answer

They are diastereomers.

Question 19

Which of the following statements about the energy diagram of molecular orbitals in ethylene ($$\mathrm{C_2H_4}) is $$correct?

Accepted Answer

The $$\sigma$$ bonding orbital is lower in energy than the $$\pi$$ bonding orbital.

Question 20

A solution contains both acetic acid ($$pK_a = 4.8) $$and phenol ($$pK_a = 10.0). $$Which will be deprotonated first as a strong base is added, and why?

Accepted Answer

Acetic acid, because it is a stronger acid

CHEM 261 Organic Chemistry Learning Objectives: Study Guide

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드