Polarity Flashcards
What determines how substances interact with each other?
polarity
Are polar bonds necessary for a molecule to be polar?
yes, but they’re not sufficient
What does a molecule also need in order for it to be polar?
needs to have a net dipole moment
What is a net dipole moment?
when there is an overall partial positive charge on one end of the molecule and a partial negative charge on the other end of the molecule
What is no net dipole moment?
Pulling of the forces cancel each other (nonpolar)
What is the polarity, basis of cancelation, and net dipole moment of linear geometry?
nonpolar
cancels out
no net dipole moment
What is the polarity, basis of cancelation, and net dipole moment of bent geometry?
polar
does not cancel out because of asymmetry
net dipole moment
What is the polarity, basis of cancelation, and net dipole moment of trigonal planar geometry?
nonpolar
cancels out
no net dipole moment
What is the polarity, basis of cancelation, and net dipole moment of tetrahedral geometry?
nonpolar
cancels out
no net dipole moment
What is the polarity, basis of cancelation, and net dipole moment of trigonal pyramidal geometry?
polar
does not cancel out
net dipole moment
What do lone pairs on an the central atom affect?
polarity and could potentially have a net dipole moment
Does asymmetry make a difference in identifying polarity?
yes, due to the force on a central atom with lone pairs
What is symmetry?
Pulling of the forces are even when there is no lone pair on the central atom
What plane is nonpolar in?
same plane
What plane is polar in?
not in same plane (asymmetric)
What does a molecule need in order to be polar?
polar bonds and a net dipole moment
How do you know if a molecule has polar bonds?
If the difference in electronegativity for the atoms in a bond is greater than 0.5
What kind of bond is it when ∆electronegativity is below 0.5?
nonpolar covalent bond
What kind of bond is it when ∆electronegativity is between 0.5 and 2?
polar covalent bond
What kind of bond is it when ∆electronegativity is above 2?
fully polar
Can a molecule be polar if it has no net dipole moment?
no
Do PFAs molecules have net dipole moments?
no, therefore is nonpolar
What does intramolecular mean?
within molecule
What does intermolecular mean?
between molecules
What are london dispersion forces?
attraction between two temporary, instantaneous, non-permanent dipoles (temporary)
What is dipole-dipole attraction?
attraction between a partially positive portion of one molecule and partially negative portion of a different molecule
What is the only interaction available for nonpolar molecules?
london dispersion forces
How strong are london dispersion forces?
fleeting and weak
How strong are dipole-dipole forces?
intermediate strength
What kind of bond do you need for a dipole-dipole attraction to exist?
polar bond
What will there be in a dipole-dipole attraction?
attraction or repulsion
What is hydrogen bonding responsible for?
water behavior+properties
What is a special case of dipole-dipole interaction?
hydrogen bonding
What elements are reserved for hydrogen bonding?
when hydrogen is bonded to nitrogen, oxygen, or fluorine
How strong are hydrogen bonds?
strong interaction
Are london dispersion forces intramolecular or intermolecular?
intermolecular
Are hydrogen bondings intramolecular or intermolecular?
intermolecular
Are dipole-dipole attractions intramolecular or intermolecular?
intermolecular
