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Question 1

Key Components of Substitution Reactions

Answer 1

Substrate:
The substrate is an sp³ hybridized carbon atom bonded to a leaving group (X− ).
Example:
R−X, where
X is the halogen acting as the leaving group.
Nucleophile (Nu−):
A nucleophile donates a pair of electrons to form a bond with the electron-deficient carbon atom.
Examples:
OH−, SH−,
OCH3−.
Leaving Group (X−):
The leaving group detaches from the carbon atom, taking the bonding electrons with it.
A good leaving group is typically a weak base (e.g.,
Cl−, Br−, I−).

Question 2

General Reaction

Answer 2

R−X+Nu −→R−Nu+X −

The nucleophile replaces the halogen in the substrate.
The leaving group leaves, forming a negatively charged ion (X−).

Question 3

Examples of Substitution Reactions

Answer 3

Question 4

What type of carbon atom is involved in substitution reactions?

Answer 4

Answer: An sp³ hybridized carbon atom.v

Question 5

What makes a good leaving group?

Answer 5

What makes a good leaving group?
Answer: A weak base, such as
Cl−, Br−, or I−.

Question 6

In the reaction
CH3−Cl+OH−→CH3−OH+Cl-

Answer 6

, what is the nucleophile?
Answer:
OH−(hydroxide ion).

Question 7

What is the product when
CH3CH2−I reacts with
SH−?

Answer 7

Answer: Ethyl thiol (
CH3CH2−SH).

Question 8

What is the leaving group in the reaction
CH3CH2−Br+OCH3−→CH3CH2−OCH3+Br−?

Answer 8

Answer: Bromide ion (
Br− ).