2nd Year Chemistry Chapter 14 TestSPECTROSCOPY-2 NMR

Q1. Multiple choice questions (Attempt all · 9 × 1 = 9)

1. Deuterated solvents are used in to:

   1. Increase magnet strength

   2. Split the signals

   3. Provide a reference signal

   4. Avoid solvent signal interference

2. What is the splitting pattern for a proton with 2 neighbouring protons (n = 2)?

   1. Singlet

   2. Doublet

   3. Triplet

   4. Quartet

3. Splitting is typically not observed for O-H or N-H protons because of:

   1. NMR-inactivity

   2. Longer bond

   3. Deuterated solvent

   4. Rapid chemical exchange

4. The chemical shift  of a peak identifies the:

   1. Number of adjacent carbons

   2. Functional group environment (C=C, C=O, etc.)

   3. Molecule's symmetry

   4. Number of protons

5. The primary purpose of measuring the peak area in is to find the:

   1. Chemical shift

   2. Number of neighboring protons

   3. Total carbon atoms

   4. Relative number of protons

6. In the n+1 splitting rule, 'n' represents the number of protons on:

   1. The entire molecule 

   2. The carbon being analyzed

   3. Adjacent carbon atoms

   4. The signal's total area

7. Chemical shift in the spectroscopy is measured relative to TMS and is expressed in:

   1. Tesla (T)

   2. Hertz (Hz)

   3. Parts per million (ppm)

   4. Degrees Celsius

8. The number of peaks in a spectrum equals the number of:

   1. Total carbon atoms

   2. Chemically non-equivalent carbons

   3. Adjacent hydrogen atoms

   4. atoms

9. NMR relies on the magnetic properties of nuclei known as:

   1. Chemical shift

   2. Nuclear density

   3. Nuclear spin

   4. Signal intensity