Why does water boil higher than H₂S?
Water forms hydrogen bonds; H₂S only London forces → weaker.
Why does NCl₃ boil higher than NF₃?
NCl₃ has stronger London forces (bigger molecules). NF₃ more polar but weaker London forces.
Why do boiling temps increase from Cl₂ to I₂?
Bigger molecules → stronger London forces.
Explain boiling differences: HF, H₂O, CH₄.
HF & H₂O hydrogen bond; H₂O strongest network; CH₄ only London forces.
Why ethanol boils far higher than ethene?
Ethanol forms hydrogen bonds; ethene only London forces.
Why methanol + water fully miscible?
Hydrogen bonds form between them.
Why 2,2-dimethylpropane boils lower than pentane?
More spherical → weaker London forces.
How do London forces form?
Temporary dipole induces dipoles → attraction.
Why Br₂ boils higher than Cl₂?
More electrons → stronger London forces.
Why NaCl less soluble in methanol?
Ion–dipole interactions weaker in methanol than water.
Why hydrogen bonding makes ice less dense?
Open lattice holds molecules further apart.
Strongest intermolecular force between methanol & water?
Hydrogen bonding.
Why phenol nitrates easier than benzene?
O– activates ring via lone pair donation → increases electrophilic attack.
Why 4-nitrophenol boils higher than 2-nitrophenol?
Stronger intermolecular hydrogen bonding (less intramolecular).
Interactions when NaClO dissolves?
Hydration: ions attracted to polar water (ion–dipole).
Why ethanol soluble but chloroethane not?
Ethanol forms hydrogen bonds; chloroethane only London forces.
Why hydrazine soluble in water?
Forms hydrogen bonds via –NH₂ groups.
Explain water anomalies: boiling & density.
Hydrogen bonding strong; open ice lattice less dense.
How do London forces arise ?
Random movement of electrons results in a temporary dipole formation, which induces a dipole in an adjacent molecule
