Boiling Points
Which has a higher boiling point: ethanol or dimethyl ether?
Ethanol (because of hydrogen bonding).
Which is more soluble in water: methanol or ethoxyethane (diethyl ether)?
Methanol (strong hydrogen bonding with water).
What functional group do alcohols contain?
Hydroxyl (-OH) group.
Ethers have stronger intermolecular forces than alcohols.
False (alcohols have hydrogen bonding, making them stronger).
What type of intermolecular force causes alcohols to have higher boiling points than ethers?
Hydrogen bonding.
True or False: Small alcohols are generally more water-soluble than ethers.
True (alcohols form hydrogen bonds with water).
What functional group do ethers contain?
An oxygen atom bonded to two alkyl or aryl groups (R-O-R').
Ethers are more soluble in water than alcohols.
False (alcohols form stronger hydrogen bonds with water).
Why do ethers generally have lower boiling points than alcohols of similar molecular weight?
Ethers lack hydrogen bonding between molecules, making their intermolecular forces weaker.
Which would dissolve better in water: ethanol or diethyl ether?
Ethanol (strong hydrogen bonding with water).
What is the IUPAC name for CH₃CH₂OCH₂CH₃?
Diethyl ether.
Alcohols have higher boiling points than ethers of similar molecular weight.
True (due to hydrogen bonding).
Why does methanol (CH₃OH) have a lower boiling point than butanol (C₄H₉OH), even though both are alcohols?
Methanol has fewer carbon atoms, leading to weaker London dispersion forces despite hydrogen bonding.
Why are small ethers (like dimethyl ether) slightly soluble in water but large ethers are not?
Small ethers have lone pairs on oxygen that weakly interact with water, but larger ethers have more nonpolar hydrocarbon chains, reducing solubility.
What is the IUPAC name for CH₃CH(OH)CH₃?
Propan-2-ol (Isopropanol).
Alcohols can act as both hydrogen bond donors and acceptors.
True (the -OH group can donate and accept hydrogen bonds).
Rank the following in order of boiling points (highest to lowest): propanol, diethyl ether, butanol.
Butanol > Propanol > Diethyl ether (longer alcohol chains increase boiling points).
Explain why alcohols are both hydrophilic and hydrophobic, while ethers are mostly hydrophobic.
Alcohols have a hydrophilic (-OH) group and a hydrophobic hydrocarbon chain, while ethers lack an -OH group and are mainly nonpolar.
What is the difference between primary, secondary, and tertiary alcohols?
Primary: -OH attached to a carbon bonded to one other carbon; Secondary: bonded to two carbons; Tertiary: bonded to three carbons.
Ethers generally have stronger intermolecular forces than alcohols.
False (ethers lack hydrogen bonding, making their forces weaker).