Reactivity and electronic structure Flashcards
valence e-
number of electrons
electronic structure of H
wants 2 e- around nucleus to be stable
electronic structure of C, N, O, F
wants 8 e- around nucleus
also P, S, Br, I
example of electronic structure - methane
C shares with H atoms therefore valence shell for C if full when sharing e-
finding e- pairs
work from given chemical structure
find e- and deduce possible charges
has the octet rule
radicals
does not fulfil octet rule
highly reactive radicals
does not fulfil octet group
electronegativity function
predict e- distribution (polarisation)
resonance structure arrangement
arrangement remains same but e- distribution is different
sigma bond is also same
resonance structure
when molecule is represented by 2/more hybrid structure
different in position of e- only
making resonance function
- put all lone pairs and formal charges
- moving e- where pi e- in double bond in lone pair
- don’t make 5 bonded atom - including lone pair
curly arrows
movement of e- pair from chemical bond - bond broken
curly arrows falling between atoms
chemical bond formed
if e- falls on atom
lone pair created
importance of curly arrows / resonance structure
shows stability of molecules/ reactivity of molecular structure