6.6.1 Properties of Alcohols

• Alcohols are characterized by the presence of a hydroxyl (-OH) functional group.hydroxyl
• The -OH group influences the physical and chemical properties of alcohols.
• The boiling points of alcohols are higher than alkanes of similar size due to hydrogen bonding
• Alcohols are generally soluble in water due to hydrogen bonding with water molecules.
• Alcohols are weakly acidic due to their ability to donate a hydrogen ion
• The physical properties of alcohols are significantly influenced by the hydroxyl functional group.hydroxyl
• Match the property with its explanation for alcohols:

  Boiling Point ↔️ Hydrogen bonding between molecules

  Solubility in Water ↔️ Hydrogen bonding with water
• Alcohols are better solvents for polar substances compared to alkanes.
• Hydrogen bonding in alcohols occurs between the -OH group and lone pairs on oxygen atoms of another molecule.oxygen
• What type of intermolecular force occurs between alcohol molecules?

  Hydrogen bonding
• Hydrogen bonding in alcohols occurs between the hydroxyl (-OH) group of one molecule and the lone pairs on the oxygen atoms of another, leading to higher boiling points compared to alkanes
• What effect does hydrogen bonding have on the boiling points of alcohols compared to alkanes?

  Higher boiling points
• Alcohols are characterized by the presence of a hydroxyl (-OH) functional group.
• Match the property of alcohols with its explanation:

  Higher boiling point ↔️ Hydrogen bonding requires more energy

  More soluble in water ↔️ -OH group forms hydrogen bonds with water

  Weakly acidic ↔️ -OH group can donate a proton (H+)
• Hydrogen bonds in alcohols form between the hydroxyl (-OH) group and the lone pairs on the oxygen atom of another, elevating the boiling point compared to alkanes.
• Order the types of hydrogen bonds in alcohols based on their effects:

  1️⃣ Between alcohol molecules (raises boiling point)

  2️⃣ Between alcohol and water (enhances solubility)
• The strong hydrogen bonds in alcohols require more energy to break, leading to higher boiling points.
• Why are the boiling points of alcohols higher than alkanes?

  Hydrogen bonding
• Match the type of alcohol with its boiling point:

  Primary alcohol ↔️ Highest boiling point

  Secondary alcohol ↔️ Medium boiling point

  Tertiary alcohol ↔️ Lowest boiling point
• The number of alkyl groups attached to the carbon bearing the -OH group affects the boiling point, with primary alcohols having the highest and tertiary alcohols the lowest
• As the carbon chain length of an alcohol increases, its boiling point rises due to increased van der Waals forces.
• What is the boiling point of ethanol ($C_{2}H_{5}OH$)?


  78.37 °C
• As the carbon chain length of an alcohol increases, its solubility in water decreases
• Match the type of alcohol with its solubility in water:

  Primary alcohol ↔️ Highly soluble

  Secondary alcohol ↔️ Moderately soluble

  Tertiary alcohol ↔️ Low solubility
• Primary alcohols can be oxidized to aldehydes or carboxylic acids.
• What type of reaction converts alcohols to alkenes?

  Dehydration
• Order the steps of alcohol oxidation based on alcohol type:

  1️⃣ Primary alcohols oxidize to aldehydes or carboxylic acids

  2️⃣ Secondary alcohols oxidize to ketones

  3️⃣ Tertiary alcohols do not oxidize easily
• Primary alcohols can be oxidised to aldehydes or carboxylic acids
• Tertiary alcohols are easily oxidised.

  False
• Order the conditions required for dehydration of alcohols from most to least stringent.

  1️⃣ Primary alcohols require strong heating and catalysts.

  2️⃣ Secondary alcohols dehydrate under milder conditions.

  3️⃣ Tertiary alcohols dehydrate under even milder conditions.
• The hydroxyl group in alcohols is polar and can form hydrogen bonds.
• Alcohols have higher boiling points than alkanes due to hydrogen bonding
• Why is ethanol more soluble in water than ethane?

  Forms hydrogen bonds with water
• Hydrogen bonding in alcohols occurs between the hydroxyl group and lone pairs on oxygen atoms.
• Alcohols have higher boiling points than alkanes because hydrogen bonding requires more energy
• Hydrogen bonding in alcohols affects both boiling points and solubility.
• Order the types of alcohols from highest to lowest boiling point.

  1️⃣ Primary

  2️⃣ Secondary

  3️⃣ Tertiary
• Primary alcohols have the strongest hydrogen bonds and the highest boiling points.
• Alcohols are soluble in water because the hydroxyl group forms hydrogen bonds with water molecules.
• Match the type of alcohol with its solubility in water.

  Primary Alcohol ↔️ High Solubility

  Secondary Alcohol ↔️ Moderate Solubility

  Tertiary Alcohol ↔️ Low Solubility