Spectroscopic techniques

Calculate the index of hydrogen deficiency for a compound with the molecular formula C6H6O.

• 1

• 2

• 3

• 4

Deduce the index of hydrogen deficiency of ethylamine, C2H5NH2.

• 0

• 1

• 2

• 3

Cholesterol has the molecular formula C27H46O.

What is the index of hydrogen deficiency of cholesterol?

• 3

• 6

• 4

• 5

Retinal has the molecular formula C20H28O. It contains five C=C double bonds and one C=O bond. How many rings does retinal possess?

• 1

• 2

• 3

• 4

A hydrocarbon contains 85.7% carbon by mass. Its 1H NMR spectrum shows two signals in the ratio of 3:1.

Which compound is consistent with this data?

• but-1-ene

• 2-methylprop-1-ene

• propane

• propene

What information can be obtained from the number of peaks in the H NMR spectrum of a compound?

• The number of different chemical environments occupied by the protons in one molecule of the compound.

• The number of hydrogen atoms in one molecule of the compound.

• The number of different functional groups in one molecule of the compound

• the number of carbon atoms in one molecule of the compound

It is used to identify the bonds in a molecule.

• Infrared spectroscopy

• mass spectroscopy

• x ray crystallography

• NMR

It is used to determine relative atomic and molecular masses.

• infrared spectroscopy

• mass spectroscopy

• NMR

• index of hydrogen deficiency

In a mass spectrum, the fragment with the highest mass belongs to _________.

• electron

• molecule

• anion

• molecular ion

Its fragment has a mass of 15.

• OH-

• H2O

• COOH-

• CH3+