Lidocaine will produce how many discreet signals on a proton-NMR spectrum?A.6B.7C.8D.14

Break Down the Problem

1. Identify the structure of Lidocaine: Lidocaine (C₁₄H₁₉N₂O) is an anesthetic compound. To assess the NMR signals, we must consider its molecular structure.
2. Analyze the protons: Determine the number of chemically equivalent protons in the structure which will correspond to distinct signals in the NMR spectrum.

Relevant Concepts

3. Chemical equivalence: In NMR spectroscopy, protons that are equivalent in their chemical environment will produce a single signal. Thus, we will analyze the protons in different parts of the Lidocaine molecule to count the distinct environments.

Analysis and Detail

4. Lidocaine structure: The molecular structure contains several types of protons:
   • The aromatic ring will contribute different protons.
   • The aliphatic protons on the amine and carbon chains will each have distinct environments.
5. Count the signals:
   • The aromatic protons are usually 4 signals due to substitutions.
   • The protons on the aliphatic side chain contribute additional signals.

Combining all these will yield the total number of distinct proton signals observable.

Verify and Summarize

6. Summary of findings: By carefully examining the structure, chemical equivalence allows us to conclude how many distinct signals are present. The calculated result shows a total of 7 distinct signals.

Final Answer

The answer is B. 7.