Mass Spectrometry and IR

What is the average atomic mass for this element?

• 10 amu
• 10.8 amu
• 19.9 amu
• 11 amu

Which of the following statements best describes the base peak in a mass spectrum?

• The peak from the most stable radical.

• The peak of highest intensity.

• The peak from the molecule minus an electron.

• The peak from the species that has the isotope with the highest atomic number.

If the molecular ion, M⁺ m/z = 136 and M+2⁺ at m/z = 138 of approximately equal intensity, which molecule is it?

• C₆H₁₃OCl

• C₁₀H₁₆

• C₉H₁₂O

• C₄H₉Br

What is the infrared bond type for C−C, C−O, C−N, and C−X single-bond vibrations.

• 4000 to 2500 cm⁻¹

• 2500 to 2000 cm⁻¹

• 2000 to 1500 cm−¹

• below 1500 cm⁻¹

What is the infrared bond type for C=O, C=N, and C=C bond absorptions.

• 4000 to 2500 cm⁻¹

• 2500 to 2000 cm⁻¹

• 2000 to 1500 cm−¹

• below 1500 cm⁻¹

What is the infrared bond type for N−H, C−H, and O−H stretching and bending motions.

• 4000 to 2500 cm⁻¹

• 2500 to 2000 cm⁻¹

• 2000 to 1500 cm−¹

• below 1500 cm⁻¹

What is the infrared bond type for triple bond stretching vibrations.

• 4000 to 2500 cm⁻¹

• 2500 to 2000 cm⁻¹

• 2000 to 1500 cm−¹

• below 1500 cm⁻¹

Select the most reasonable formula for the following mass spectral data. M⁺ m/z = 136 and M⁺ at m/z = 138 of approximately equal intensity

• C₄H₉Br

• C₆H₁₃OCl

• C₁₀H₁₆

• C₉H₁₂O

MATCH a structure from the list below to the following IR spectra.

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• 

What kind of particles are used in mass spectrometry?

• Anions
• Cations