4.1.5 Analytical Techniques

Where is the base peak?

• 57 amu
• 29 amu
• 72 amu
• 43 amu

What kind of particles are used in mass spectrometry?

• Anions
• Cations

What substance does this mass spectra represent?

• hexane

• pentane

• butane

• pentene

What cation does the "83" peak represent?

• CH3COCHC

• CH3COCHCCH2

• CH3COCHCCH3

• CH3COC

In this mass spectra what does the M+1 and M+2 peaks represent?

• They represent the molecular ion that contains C isotope 13 and 14.

• They represent other fragments of the molecular ion.

• They represent the base peak.

• They represent isotopes of Carbon (13 and 14).

What is an analytical technique?

• A procedure that uses machines.

• A procedure that allows you to investigate a known compound

• A procedure that allows you to investigate an unknown substance and discover its identity.

• A procedure that allows you to discover new elements.

What ratio does the mass spectrometer detect?

• mass of main radical

• mass of molecular ion

• charge to mass ratio

• mass to charge ratio

Why do the fragments help us to identify the molecule?

• The cations allow us only to identify the molecular mass.

• It is not possible to identify the exact final molecule.

• Because knowing all possible fragments help us to identify branches and possible isomers.

• Because the fragments allow us to identify the different atoms that make up the molecule.

What is the molecular weight of this compound?

• 29

• 87

• 54

• 15

Tags

NGSS.HS-PS1-7

Which of the following molecular formulas could correspond to the above mass spectrum?

• C₆H₅Br

• C₆H₅Cl

• C₆H₅CH₂Br

• C₆H₅CH₂Cl