Question 1

Which of the following statements best explains why carbon is central to organic chemistry?

Accepted Answer

Carbon has four valence electrons, allowing it to form stable covalent bonds with many elements and create complex structures.

Question 2

Given the electronic configuration of carbon as $1s^2 2s^2 2p^2$, how many unpaired electrons does a neutral carbon atom have?

Accepted Answer

Two

Question 3

Which of the following molecules contains a polar covalent bond?

Accepted Answer

$CH_3OH$

Question 4

What is the formal charge on the nitrogen atom in $NH_4^+$?

Accepted Answer

+1

Question 5

Which resonance form of the acetate ion ($CH_3COO^-$) is the major contributor?

Accepted Answer

Both forms with the negative charge on either oxygen atom contribute equally due to delocalization.

Question 6

Which of the following is a correct condensed structural formula for butan-2-ol?

Accepted Answer

$CH_3CH(OH)CH_2CH_3$

Question 7

Which statement about line-angle (skeletal) drawings is TRUE?

Accepted Answer

Each vertex or end of a line represents a carbon atom.

Question 8

What is the hybridization and geometry of the central carbon atom in $CO_2$?

Accepted Answer

sp, linear

Question 9

Which of the following best describes the bonding in ethylene ($C_2H_4$)?

Accepted Answer

Each carbon forms three sigma bonds using sp^2 hybrid orbitals and one pi bond from unhybridized p orbitals.

Question 10

Which of the following statements about rotation around bonds is correct?

Accepted Answer

Rotation is restricted around double bonds due to the presence of a pi bond.

Question 11

How many sigma and pi bonds are present in the molecule $C_2H_2$ (acetylene)?

Accepted Answer

3 sigma, 2 pi

Question 12

Which of the following is a constitutional isomer of $C_4H_{10}$?

Accepted Answer

2-methylpropane

Question 13

Which of the following pairs are geometric (cis-trans) isomers?

Accepted Answer

cis-2-butene and trans-2-butene

Question 14

Which of the following criteria is most important when determining the major resonance contributor?

Accepted Answer

The structure with the most complete octets.

Question 15

What is the bond angle in a molecule with sp^3 hybridization?

Accepted Answer

$109.5^	ext{o}$

Question 16

Which of the following best describes the difference between constitutional isomers and stereoisomers?

Accepted Answer

Constitutional isomers differ in connectivity; stereoisomers differ only in spatial arrangement.

Question 17

Which of the following statements about resonance structures is FALSE?

Accepted Answer

Resonance forms can be interconverted by moving atoms.

Question 18

Which of the following molecules has a trigonal planar geometry?

Accepted Answer

$BF_3$

Question 19

Which of the following is the correct empirical formula for glucose ($C_6H_{12}O_6$)?

Accepted Answer

$CH_2O$

Question 20

A molecule has two sigma bonds and two lone pairs on the central atom. What is the hybridization and geometry of the central atom?

Accepted Answer

sp^3, tetrahedral electron geometry

Organic Chemistry: Structure and Bonding – Chapter 1 Study Notes

Study Guide - Practice Questions