Take this Quiz: A-Level Chemistry: Organic Analysis and Synthesis | Zestly

Question 1

An unknown organic compound X produces a molecular ion peak at m/z 74 in mass spectrometry. A peak at m/z 59 is also observed. Which fragment loss corresponds to the difference between these two peaks?

Accepted Answer

Loss of a methyl group

Question 2

Which of the following reagents will produce a positive observation when reacted with propanal?

Accepted Answer

Tollens' reagent

Question 3

In proton NMR spectroscopy, why is tetramethylsilane (TMS) used as the standard reference?

Accepted Answer

Its protons are all in the same chemical environment

Question 4

An organic compound shows a broad infrared absorption peak at 3300 cm-1 and a sharp peak at 1710 cm-1. Which functional group combination is present?

Answer

Aldehyde and alkene

Answer

Alcohol and alkene

Answer

Carboxylic acid

Answer

Ester and alcohol

Question 5

In a proton NMR spectrum, a signal at 2.1 ppm appears as a quartet. What does this indicate about the neighboring protons?

Answer

There are 3 protons on the adjacent carbon atom

Answer

There are 4 protons on the adjacent carbon atom

Answer

There are 2 protons on the adjacent carbon atom

Answer

There are 0 protons on the adjacent carbon atom