Which of the following compounds is least acidic due to +M effect?
Practice Questions
1 question
Q1
Which of the following compounds is least acidic due to +M effect?
Phenol
Acetic acid
Formic acid
Benzoic acid
Phenol is less acidic compared to the other acids listed due to the +M effect of the aromatic ring, which destabilizes the negative charge on the phenoxide ion.
Questions & Step-by-step Solutions
1 item
Q
Q: Which of the following compounds is least acidic due to +M effect?
Solution: Phenol is less acidic compared to the other acids listed due to the +M effect of the aromatic ring, which destabilizes the negative charge on the phenoxide ion.
Steps: 6
Step 1: Understand what acidity means. Acidity refers to how easily a compound can donate a proton (H+).
Step 2: Identify the compounds being compared. In this case, we are looking at phenol and other acids.
Step 3: Learn about the +M effect. The +M effect (positive mesomeric effect) occurs when an electron-donating group (like an aromatic ring) stabilizes a negative charge.
Step 4: Recognize that phenol has an aromatic ring. This ring can donate electrons, which affects the stability of the phenoxide ion (the ion formed when phenol loses a proton).
Step 5: Compare the stability of the phenoxide ion to other acids. The +M effect from the aromatic ring makes the negative charge on the phenoxide ion less stable.
Step 6: Conclude that because the negative charge is destabilized by the +M effect, phenol is less acidic than the other acids listed.
