Chapter 2 Flashcards
Bonds between atoms whose electronegativities differ by less than ___ are nonpolar covalent, bonds between atoms whose electronegativities differ by ___ to ___ are polar covalent, and bonds between atoms
whose electronegativities differ by more than ___ are largely ionic
0.5, 0.5 to 2, 2
inductive effect
an atom’s ability to polarize a bond, shifting electrons IN A PI BOND in response to EN of nearby atoms
dipole moment (Greek mu)
magnitude of charge at either end of molecule times distance between charges
formal charge calculation
ve in free atom - # ve in bonded atom
resonance forms for acetate ion (H3C-C=O-O)
both oxygen atoms share the negative charge and have equal electron densities (neither of the two structures is correct by itself for which O is double bonded to C)
What differentiates two resonance forms?
placement of pi and nonbonding VEs
resonance hybrid
no jumping back and forth b/w 2 resonance forms, instead has a single unchanging structure of the 2 forms
can go from triple to double
DON’T DIFFER IN NUCLEI POSITION
Are all resonance forms equivalent?
no!
acetone - one has a C=O bond and other has C=C bond
different but both contribute to overall resonance hybrid
BUT: actual structure of hybrid resembles the more stable form
True or false: The resonance hybrid is less stable than any individual resonance
form
false
any ____ atom grouping with a ___ orbital on each atom has two resonance forms
3, p
radical
substance that contains a single, unpaired electron in one of its orbitals,
denoted by a dot