Secondary Bonds Flashcards
How does hydrogen bonding occur in H-F?
Fluorine has the highest electronegativity value on the periodic table. there is a large EN difference between H and F, meaning it is a very polar bond (large shift in electrons). A distinct partial negative charge is created on the F atom, and a distinct partial positive on the H atom. The negative and positive ends attract adjacent H-F molecules and form hydrogen bonds.
Why does ammonia have a higher boiling point than CO2?
CO2 is a linear molecule (non-polar), meaning CO2 molecules are attracted to each other through dispersion forces. NH3 is an asymmetrical, polar molecule meaning it has positive and negative regions. NH3 forms hydrogen bonds with other NH3 molecules, which are the strongest intermolecular forces. This means NH3 would need more heat energy to break these bonds (higher boiling point).
Write an equation for the dissociation of NaOH in water.
NaOH(s) + (aq) —-> Na+(aq) + OH- (aq)
How do dispersion forces occur?
Electrons in non-polar molecules are usually evenly distributed. At a particular point in time the electrons are unevenly distributed and a temporary dipole is formed. This brings about an induced dipole in an adjacent molecule.
How do dipole-dipole interactions occur?
Polar molecules have a partially positive and partially negative region. The partially positive end of one molecule will attract and bond with the partially negative end of another molecule, forming a dipole-dipole bond.
