Mass Spectroscopy PreTest

What do the peaks on the mass spectrum represent?

• anions

• mass of positively charged fragments

• mass of negatively charged fragments

• numbers of electrons

Which of the following is NOT a step in the operation of a mass spectrometer?

• Accelerate,

• Deflect

• Radiate

• Ionize

Tags

NGSS.HS-PS2-5

The above Mass Spectra of an unknown substance contains an M⁺ peak of 64 and an M+2 Peak. What is the molecular weight of this substance?

• 29

• 49

• 64

• 66

Tags

NGSS.HS-PS1-2

What is the molecular weight of this compound?

• 29

• 87

• 54

• 15

Tags

NGSS.HS-PS1-7

What are the steps of operation in the mass spectrometer?

• Accelerate, Deflect,Ionize, Detect
• Deflect,Ionize, Accelerate, Detect
• Ionize, Accelerate, Deflect, Detect
• Detect, Accelerate, Deflect, Ionize

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

Which species would get deflected by the greatest degree in the mass spectrometer?

• ¹²C⁺
• ¹³C⁺
• ¹³C²⁺
• ¹⁴C⁺

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-5

What do the heights of the peaks represent in the mass spectrum?

• number of isotopes
• relative abundance of each isotope
• average atomic mass
• charge:mass ratio

Based on the mass spectrum, which isotope of chlorine is most abundant?

• ³⁵Cl

• ³⁷Cl

• ⁷⁰Cl

• ⁷²Cl

Where is the base peak?

• 57 amu
• 29 amu
• 72 amu
• 43 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.