Textbook Question
Identify the arrows shown by type and predict the product that should result.
(a)
3. Acids and Bases
Reaction Mechanism
4:35 minutesProblem 15a,b
Textbook Question
Use curved arrows to show the movement of electrons in the following reaction steps
a. 
b. 
Verified step by step guidance1
Step 1: Analyze reaction A. The reaction involves formic acid (HCOOH) and hydronium ion (H₃O⁺). The hydronium ion acts as an acid, donating a proton (H⁺) to the oxygen atom of the carbonyl group in formic acid. Use a curved arrow to show the movement of electrons from the lone pair on the oxygen atom of the carbonyl group to the hydrogen atom of H₃O⁺.
Step 2: After the proton transfer in reaction A, the oxygen atom in the carbonyl group becomes positively charged. The hydronium ion loses a proton and forms water (H₂O). Use a curved arrow to show the breaking of the O-H bond in H₃O⁺, with the electrons moving to the oxygen atom.
Step 3: Analyze reaction B. The reaction involves cyclopentene and bromonium ion (Br⁺). The double bond in cyclopentene acts as a nucleophile, attacking the positively charged bromonium ion. Use a curved arrow to show the movement of electrons from the π-bond of the double bond to the bromonium ion.
Step 4: After the attack in reaction B, the bromonium ion forms a bond with one of the carbon atoms in the double bond, creating a carbocation intermediate. Use a curved arrow to show the formation of the new C-Br bond.
Step 5: The bromonium ion stabilizes the carbocation intermediate by donating a lone pair of electrons to the positively charged carbon atom. Use a curved arrow to show the movement of electrons from the bromonium ion to the carbocation, completing the reaction.
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Video duration:
4mKey Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Curved Arrows in Mechanisms
Curved arrows are used in organic chemistry to represent the movement of electrons during chemical reactions. The tail of the arrow indicates the electron source, while the head points to the electron destination. This notation helps visualize how bonds are formed and broken, providing insight into the reaction mechanism.
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General Mechanism
Acid-Base Reactions
Acid-base reactions involve the transfer of protons (H+) between reactants. In these reactions, acids donate protons, while bases accept them. Understanding the role of acids and bases is crucial for predicting the products of reactions and for drawing accurate reaction mechanisms using curved arrows.
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02:49The Lewis definition of acids and bases.
Electrophiles and Nucleophiles
Electrophiles are electron-deficient species that seek electrons, while nucleophiles are electron-rich species that donate electrons. In the context of the provided reactions, identifying these species is essential for understanding how they interact and the direction of electron flow, which is illustrated by the curved arrows in the reaction mechanisms.
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03:Nucleophile or Electrophile
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