Question 1

Which experiment disproved the 'vital force' theory in organic chemistry, and what compound was synthesized?

Accepted Answer

Friedrich Wöhler's synthesis of urea from ammonium cyanate in 1828

Question 2

According to modern definitions, organic chemistry is best described as:

Accepted Answer

The chemistry of carbon compounds

Question 3

Which of the following statements about carbon is correct?

Accepted Answer

Carbon is always tetravalent, forming four bonds

Question 4

What is the main difference between a covalent bond and an ionic bond?

Accepted Answer

A covalent bond involves sharing electrons, while an ionic bond involves transfer of electrons

Question 5

Which of the following is the correct electron configuration for a ground-state carbon atom?

Accepted Answer

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

Question 6

Which type of atomic orbital overlap leads to the formation of a sigma ($\sigma$) bond in a hydrogen molecule ($H_2$)?

Accepted Answer

$s$-$s$ overlap

Question 7

Which of the following best explains why the bond angles in methane ($CH_4$) are $109.5^\circ$?

Accepted Answer

The central carbon atom uses $sp^3$ hybrid orbitals, resulting in a tetrahedral geometry

Question 8

Which of the following molecules has a trigonal planar geometry around the central atom?

Accepted Answer

Ethylene ($C_2H_4$)

Question 9

What is the formal charge on the nitrogen atom in the ammonium ion ($NH_4^+$)?

Accepted Answer

$0$

Question 10

Which of the following statements about resonance is correct?

Accepted Answer

Resonance structures differ only in the arrangement of electrons, not atoms

Question 11

Which of the following is a correct statement about $\pi$ bonds?

Accepted Answer

$\pi$ bonds are formed by sideways overlap of $p$ orbitals

Question 12

Which of the following best describes the geometry and hybridization of the central carbon atom in acetylene ($C_2H_2$)?

Accepted Answer

Linear geometry, $sp$ hybridization

Question 13

Which of the following bonds is considered nonpolar based on electronegativity differences?

Accepted Answer

C–H bond

Question 14

Given the following $pK_a$ values: $CH_4$ ($\sim -50$), $NH_3$ ($36$), $H_2O$ ($15.7$), $HF$ ($3.2$), which is the strongest acid?

Accepted Answer

$HF$

Question 15

Which of the following statements about Lewis acids and bases is correct?

Accepted Answer

A Lewis acid accepts a lone pair of electrons to form a new bond

Question 16

Which of the following molecules is more acidic: $CH_3CH_2OH$ or $CH_3COOH$? Why?

Accepted Answer

$CH_3COOH$, because the carboxyl group stabilizes the conjugate base via resonance

Question 17

Which of the following best explains why $sp^2$ hybridized carbons have bond angles close to $120^\circ$?

Accepted Answer

Three $sp^2$ hybrid orbitals arrange themselves in a trigonal planar geometry to minimize electron repulsion

Question 18

Which of the following is a correct statement about the octet rule as it applies to carbon?

Accepted Answer

Carbon tends to form four bonds to achieve a filled valence shell of eight electrons

Question 19

Which of the following is a valid rule for drawing resonance structures?

Accepted Answer

Only electrons move; the positions of atoms remain unchanged

Question 20

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

Accepted Answer

$\sigma$ bonds are formed by head-on overlap, while $\pi$ bonds are formed by sideways overlap of $p$ orbitals

Organic Chemistry Chapter 1: Structure and Bonding – Comprehensive Study Notes

Study Guide - Practice Questions