Question 1

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the highest energy?

Accepted Answer

Ultraviolet radiation has higher energy than radio waves, infrared, and visible light.

Question 2

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 216

Accepted Answer

The mass spectral data indicates a molecular ion peak at m/z = 216, which suggests a molecular formula of C14H18BrS2 or C16H16ClSO based on calculating the possible combinations of atoms and their respective isotopic masses. Option B contains the correct combination and number of atoms that match the molecular formula. The other options either have too many or too few atoms, or contain elements that are not consistent with the data.

Question 3

Which of the following compounds gives an infrared spectrum with no significant peaks at ˜3300 cm−¹ or 1600−1680 cm−¹?

Accepted Answer

B

Question 4

Which of the following does not involve the interaction of molecules with electromagnetic energy?

Accepted Answer

Mass spectrometry involves the ionization and separation of molecules based on their mass-to-charge ratio, and does not directly involve interaction with electromagnetic radiation. In contrast, infrared and ultraviolet spectroscopy involve the interaction of molecules with specific ranges of electromagnetic radiation, and nuclear magnetic resonance spectroscopy involves the interaction of atomic nuclei with a strong magnetic field and radiofrequency radiation.

Question 5

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

Accepted Answer

The base peak in a mass spectrum is the peak of highest intensity. It is often used as a reference peak to compare the intensity of other peaks in the spectrum.

Question 6

Which of the following compounds gives an infrared spectrum with peaks at 3000−3500 cm−¹ and ˜1750 cm−¹?

Accepted Answer

The answer of Which of the following compounds gives an...

Question 7

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (sharp peak) and 2150 cm−¹ (sharp peak)?

Accepted Answer

The answer of Which of the following compounds gives an...

Question 8

Which of the following compounds gives an infrared spectrum with a peak at strong 1730 cm−¹?

Accepted Answer

The answer of Which of the following compounds gives an...

Question 9

What is the horizontal axis of a mass spectrum?

Accepted Answer

The horizontal axis of a mass spectrum represents mass/charge (m/z) because the mass spectrometer measures the ratio of mass to charge of ions generated from the sample.

Question 10

Which of the following bonds gives rise to a strong absorbance near 1700 cm−¹ in the infrared spectrum?

Accepted Answer

The bond that gives rise to a strong absorbance near 1700 cm−1 in the infrared spectrum is the carbonyl bond, which is C=O. This bond arises in various functional groups such as ketones, aldehydes, carboxylic acids, and esters. The other bonds listed do not absorb strongly near 1700 cm−1 in the infrared spectrum.

Question 11

The amount of energy in infrared light corresponds to:

Accepted Answer

Infrared light has a wavelength that corresponds to the vibrational energy of molecules, so it is able to increase certain molecular motions, such as bond vibrations, in organic molecules. This is why infrared spectroscopy is commonly used to identify functional groups in organic molecules.

Question 12

Which of the following bonds undergoes stretching at the highest frequency?

Accepted Answer

The C=O bond undergoes stretching at the highest frequency among the given options because it has the highest bond order and bond strength. The C=O bond also has a high dipole moment due to the electronegativity difference between C and O atoms, which contributes to the high stretching frequency.

Question 13

Which of the following bonds undergoes stretching at the highest frequency?

Accepted Answer

The answer of Which of the following bonds undergoes stretching...

Question 14

Which of the following compounds gives an infrared spectrum with a peak at ˜1750 cm−¹, but no significant peaks at 3000−3500 cm−¹ or 1050−1250 cm−¹?

Accepted Answer

The peak at ˜1750 cm−¹ suggests the presence of a carbonyl group (C=O), which is characteristic of compounds such as ketones, aldehydes, and carboxylic acids. Out of the four choices, only compound B has a carbonyl group at the appropriate frequency range without any significant peaks at 3000−3500 cm−¹ (which would suggest the presence of -OH or -NH groups) or 1050−1250 cm−¹ (which would suggest the presence of C-O or C-N bonds).

Question 15

The amount of energy in electromagnetic radiation is related to the frequency and wavelength of the radiation. High energy radiation, like gamma rays, is of:

Accepted Answer

According to the electromagnetic spectrum, high energy radiation, like gamma rays, has a high frequency and short wavelength. Therefore, choice C is the correct answer.

Question 16

What is the vertical axis of a mass spectrum?

Accepted Answer

The vertical axis of a mass spectrum represents the abundance or intensity of ions detected, typically reflecting the number of ions of a particular mass-to-charge ratio.

Question 17

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 101

Accepted Answer

The formula C₆H₁₅N fits the mass spectral data, as it has peaks at m/z = 101, which corresponds to the presence of sulfur () and nitrogen (^{). The other options do not have the correct combination of elements to explain the observed peaks.}

Question 18

Examining the infrared spectrum of a compound allows us to:

Accepted Answer

The infrared spectrum of a compound provides information about the types of functional groups present in the compound. This information can be used to identify the compound and to predict its reactivity and physical properties. The other choices are not typically determined by examining the infrared spectrum.

Question 19

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (strong, broad peak) and 1640 cm−¹ (sharp, weak peak)?

Accepted Answer

The answer of Which of the following compounds gives an...

Question 20

What are the units for electromagnetic radiation used in infrared spectroscopy?

Accepted Answer

Infrared spectroscopy typically uses wavenumbers for units, which are expressed in inverse centimeters (cm⁻¹), to quantify the frequency of vibrations.

Quiz 10: Structure Determination: Mass Spectrometry, Infrared Spectroscopy, and Ultraviolet Spectroscopy

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the highest energy?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 216

Which of the following compounds gives an infrared spectrum with no significant peaks at ˜3300 cm−¹ or 1600−1680 cm−¹?

Which of the following does not involve the interaction of molecules with electromagnetic energy?

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

Which of the following compounds gives an infrared spectrum with peaks at 3000−3500 cm−¹ and ˜1750 cm−¹?

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (sharp peak) and 2150 cm−¹ (sharp peak) ?

Which of the following compounds gives an infrared spectrum with a peak at strong 1730 cm−¹?

What is the horizontal axis of a mass spectrum?

Which of the following bonds gives rise to a strong absorbance near 1700 cm−¹ in the infrared spectrum?

The amount of energy in infrared light corresponds to:

Which of the following bonds undergoes stretching at the highest frequency?

Which of the following bonds undergoes stretching at the highest frequency?

Which of the following compounds gives an infrared spectrum with a peak at ˜1750 cm−¹, but no significant peaks at 3000−3500 cm−¹ or 1050−1250 cm−¹?

The amount of energy in electromagnetic radiation is related to the frequency and wavelength of the radiation. High energy radiation, like gamma rays, is of:

What is the vertical axis of a mass spectrum?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 101

Examining the infrared spectrum of a compound allows us to:

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (strong, broad peak) and 1640 cm−¹ (sharp, weak peak) ?

What are the units for electromagnetic radiation used in infrared spectroscopy?

Quiz 10: Structure Determination: Mass Spectrometry, Infrared Spectroscopy, and Ultraviolet Spectroscopy

Which of the following regions in the electromagnetic spectrum corresponds to the radiation with the highest energy?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M+ at m/z = 216

Which of the following compounds gives an infrared spectrum with no significant peaks at ˜3300 cm−1 or 1600−1680 cm−1?

Which of the following does not involve the interaction of molecules with electromagnetic energy?

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

Which of the following compounds gives an infrared spectrum with peaks at 3000−3500 cm−1 and ˜1750 cm−1?

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−1 (sharp peak) and 2150 cm−1 (sharp peak) ?

Which of the following compounds gives an infrared spectrum with a peak at strong 1730 cm−1?

What is the horizontal axis of a mass spectrum?

Which of the following bonds gives rise to a strong absorbance near 1700 cm−1 in the infrared spectrum?

The amount of energy in infrared light corresponds to:

Which of the following bonds undergoes stretching at the highest frequency?

Which of the following bonds undergoes stretching at the highest frequency?

Which of the following compounds gives an infrared spectrum with a peak at ˜1750 cm−1, but no significant peaks at 3000−3500 cm−1 or 1050−1250 cm−1?

The amount of energy in electromagnetic radiation is related to the frequency and wavelength of the radiation. High energy radiation, like gamma rays, is of:

What is the vertical axis of a mass spectrum?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M+ at m/z = 101

Examining the infrared spectrum of a compound allows us to:

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−1 (strong, broad peak) and 1640 cm−1 (sharp, weak peak) ?

What are the units for electromagnetic radiation used in infrared spectroscopy?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 216

Which of the following compounds gives an infrared spectrum with no significant peaks at ˜3300 cm−¹ or 1600−1680 cm−¹?

Which of the following compounds gives an infrared spectrum with peaks at 3000−3500 cm−¹ and ˜1750 cm−¹?

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (sharp peak) and 2150 cm−¹ (sharp peak) ?

Which of the following compounds gives an infrared spectrum with a peak at strong 1730 cm−¹?

Which of the following bonds gives rise to a strong absorbance near 1700 cm−¹ in the infrared spectrum?

Which of the following compounds gives an infrared spectrum with a peak at ˜1750 cm−¹, but no significant peaks at 3000−3500 cm−¹ or 1050−1250 cm−¹?

Select the most reasonable formula for the compounds with the following mass spectral data. -Refer to instructions. M⁺ at m/z = 101

Which of the following compounds gives an infrared spectrum with peaks at 3300 cm−¹ (strong, broad peak) and 1640 cm−¹ (sharp, weak peak) ?