Practice Hydrogen Bonding in Chemistry
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
Hydrogen bonding is a particularly strong dipole-dipole attraction that occurs when a hydrogen atom covalently bonded to nitrogen, oxygen, or fluorine is attracted to a lone pair on a nearby nitrogen, oxygen, or fluorine atom in another (or the same) molecule.
When hydrogen is attached to a very electronegative atom, nearby molecules feel an unusually strong attraction.
Showing a random 20 of 50 problems.
Example 1
mediumSucrose dissolves easily in water. Which functional groups on sucrose are responsible, and what IMF is involved?
Example 2
easyDoes exhibit hydrogen bonding? Answer yes or no.
Example 3
easyDoes (a polar molecule with H bonded to C) participate in hydrogen bonding as a donor?
Example 4
mediumMethanol () and ethane () have similar molar masses. Which has the higher boiling point and why?
Example 5
mediumWhich would have the higher boiling point: propan-1-ol or butane ? Both are similar size.
Example 6
mediumEstimate the energy of one hydrogen bond in kJ/mol (give a typical value).
Example 7
mediumA chemist says HCl shows hydrogen bonding because it contains hydrogen. Identify the error.
Example 8
easyIn which molecule can hydrogen bonding occur: or ?
Example 9
easyWhich has a higher boiling point: water or hydrogen sulfide ?
Example 10
hardIn DNA, adenine pairs with thymine (2 H-bonds) and guanine pairs with cytosine (3 H-bonds). Which base pair is more stable thermally?
Example 11
mediumPer molecule, can a single water molecule form up to how many hydrogen bonds, and why?
Example 12
easyWhich has stronger intermolecular forces: or ?
Example 13
challengeLiquid HF has a boiling point of 19.5 °C while water boils at 100 °C, even though the individual H-F bond is more polar than O-H. Explain.
Example 14
challengeHydrogen fluoride (HF) has a higher boiling point than HCl, HBr, and HI even though it is the lightest. Reconcile this with the usual molar-mass trend.
Example 15
easyCan a water molecule act as both a hydrogen-bond donor and acceptor?
Example 16
mediumRank the boiling points of , , and from highest to lowest.
Example 17
mediumExplain why HF is a liquid at 19 °C while HCl is a gas at the same temperature.
Example 18
mediumPredict whether trimethylamine self-hydrogen-bonds.
Example 19
easyIs hydrogen bonding stronger or weaker than London dispersion forces of similar-size molecules?
Example 20
easyFill in the blank: A hydrogen bond involves a hydrogen attached to ____ being attracted to a lone pair on another ____, ____, or ____ atom.