Alcohol Chemistry Practice Flashcards

Comprehensive practice flashcards covering the preparation, structure, physical properties, and chemical reactions of alcohols based on lecture notes.

Hydration of Alkenes

A preparation method for alcohols where an alkene reacts with cold concentrated $H_2SO_4$ to form ethyl hydrogen sulphate ($CH_3-CH_2-OSO_3H$), which is then boiled with water to yield an alcohol and $H_2SO_4$.

Hydrolysis of Alkyl Halides

The reaction of an alkyl halide (e.g., $CH_3-CH_2-Cl$) with aqueous $KOH$ to form an alcohol ($CH_3-CH_2-OH$) and $KCl$.

Grignard Reagent Reaction with Formaldehyde

The reaction of a Grignard reagent ($R-Mg-X$) with formaldehyde ($HCHO$) followed by hydrolysis to form a primary ($pri-$) alcohol.

Grignard Reagent Reaction with Acetaldehyde

The reaction of a Grignard reagent with acetaldehyde (or any aldehyde except formaldehyde) to form a secondary ($sec-$) alcohol.

Grignard Reagent Reaction with Ketone

The reaction of a Grignard reagent with a ketone (e.g., propanone) to form a tertiary ($ter-$) alcohol.

Catalytic Reduction of Aldehydes

The process of using $H_2$ in the presence of a catalyst to reduce an aldehyde like $CH_3-CH_2-CHO$ to a primary alcohol.

Reducing Agents for Alcohols

Chemical agents such as $LiAlH_4$ (Lithium Aluminum Hydride) and $NaBH_4$ (Sodium Borohydride) used to reduce carbonyl compounds to alcohols.

Physical Properties: Color and Smell

Alcohols are generally colorless liquids that possess a characteristic sweet smell and a burning taste.

Hydrogen Bonding in Alcohols

The phenomenon that makes alcohols soluble in water and gives them higher boiling points than corresponding alkanes (e.g., $C_2H_5OH$ vs. $C_2H_6$).

Hybridization in Alcohols

In the structure of alcohols, both the carbon atom and the oxygen atom are $\text{sp}^3$ hybridized.

Acidity of Alcohols

Alcohols are weakly acidic and react with active metals like Sodium ($Na$) to form alkoxides (e.g., sodium ethoxide $C_2H_5ONa$) and hydrogen gas.

Order of Reactivity for $O-H$ bond breaking (ESR)

The reactivity order for electrophilic substitution reactions involving the breaking of the oxygen-hydrogen bond is $CH_3OH > \text{primary} > \text{secondary} > \text{tertiary}$.

Order of Reactivity for $C-O$ bond breaking (NSR)

The reactivity order for nucleophilic substitution reactions involving the breaking of the carbon-oxygen bond is $\text{tertiary} > \text{secondary} > \text{primary} > CH_3OH$.

Reaction with $SOCl_2$ (Thionyl Chloride)

The reaction of ethanol with $SOCl_2$ in the presence of pyridine to produce ethyl chloride ($C_2H_5Cl$), $SO_2$, and $HCl$.

Esterification

The reaction between an alcohol and a carboxylic acid in the presence of concentrated $H_2SO_4$ to produce an ester and water.

Lucas Test

A distinguishing test for alcohols where tertiary alcohols form a turbid/cloudy layer immediately, secondary alcohols after 5-10 minutes, and primary alcohols only upon heating.

Dehydration at $170\text{ }^\text{o}\text{C}$

The acid-catalyzed dehydration of ethanol using concentrated $H_2SO_4$ at $170\text{ }^\text{o}\text{C}$ to form an alkene (ethene).

Dehydration at $140\text{ }^\text{o}\text{C}$

The acid-catalyzed reaction of ethanol using concentrated $H_2SO_4$ at $140\text{ }^\text{o}\text{C}$ to form an ether (diethyl ether).

Oxidation of Secondary Alcohols

The chemical process using agents like $K_2Cr_2O_7 + \text{conc. } H_2SO_4$ that converts secondary alcohols into ketones.

Oxidation of Tertiary Alcohols

Tertiary alcohols do not undergo simple oxidation to carbonyls; instead, they give alkenes through elimination followed by oxidative cleavage.