鹵烷、醇與光譜（質譜與紅外）：練習題

Which of the following organic compounds is classified as a tertiary alcohol?

When 2-bromo-2-methylpropane is reacted with ethanolic potassium hydroxide and heated, which of the following represents the main organic product and the type of reaction taking place?

An organic compound \(X\) consists of \(68.2\%\) carbon, \(13.6\%\) hydrogen, and \(18.2\%\) oxygen by mass. Its mass spectrum shows a molecular ion peak at \(m/z = 88\).

How many structural isomers of compound \(X\) are secondary alcohols?

Which of the following describes the correct observation when phosphorus(V) chloride, \(\text{PCl}_5\), is added to a sample of butan-2-ol?

A sample of 1-iodopropane is reacted with an excess of ammonia dissolved in ethanol in a sealed tube. What is the principal organic product formed?

Classify 2-methylpropan-2-ol as a primary, secondary, or tertiary alcohol and justify your answer by describing the bonding of the carbon atom attached to the hydroxyl group.

An unknown organic liquid is tested with phosphorus(V) chloride, \(PCl_5\), and produces misty white fumes. Infrared spectroscopy of the liquid shows a broad absorption at \(3350\text{ cm}^{-1}\) but no absorption at \(1720\text{ cm}^{-1}\). Deduce the functional group present.

Explain why 1-iodobutane reacts significantly faster than 1-chlorobutane when heated with aqueous silver nitrate in ethanol, even though the \(C-Cl\) bond is more polar than the \(C-I\) bond.

A student carries out the oxidation of ethanol using acidified potassium dichromate(VI) under different laboratory conditions.
(a) Identify the organic product formed when the ethanol is heated under reflux with an excess of the oxidizing agent.
(b) State the color change that would be observed in the reaction vessel.
(c) Explain why distillation is used instead of reflux if the student intends to produce ethanal as the major product.
(d) Write a balanced chemical equation for the oxidation of ethanol to the product identified in (a), using \([O]\) to represent the oxidizing agent.

An unknown organic compound, X, has the molecular formula \(C_3H_8O\). The infrared spectrum of X shows a broad absorption peak centered at \(3330\text{ cm}^{-1}\). In the mass spectrum, the molecular ion peak is found at \(m/z = 60\), and a prominent fragment peak appears at \(m/z = 45\).
(a) Identify the functional group present in X based on the infrared data.
(b) Deduce the structure and give the IUPAC name of X.
(c) Explain the formation of the fragment at \(m/z = 45\) by identifying the species responsible and the group lost from the molecular ion.
(d) Describe the expected observation if X is reacted with phosphorus(V) chloride, \(PCl_5\).