chapter 1 Flashcards
what is a constitutional isomer?
a constitutional isomers is 2 molecules that have the same molecular formula but are bonded in a way that makes them different compounds
what is formal charge?
formal charge is associated with any atom that doesnt exhibit the appropriate # of valence electrons
when dealing with formal charge, if an atom has an extra electron what type of charge would it bear?
it would bear a positive charge (+)
when dealing with formal charge, if an atom needs an electron what type of charge does it bear?
it bears a negative charge (-)
when dealing with electronegativity and bonding if the difference in electroneg. is less than 0.5 the electrons are considered to be equally shared meaning it contains what kind of bond?
a covalent bond
when dealing with electroneg. and bonding, if the difference in elecgtroneg. is between 0.5 and 1.7 the electrons are NOT shared equally meaning it contains what kind of bond?
it contains a polar covalent bond
what is the meaning of induction in terms of electronegativity and bonding? and what does is cause?
it means the withdrawl of electrons toward oxygen shown by an arrow.
It causes the formation of partial positive and partial negative charges shown by greek symbol delta
in terms of electroneg. and bonding if the difference in electroneg. is greater than 1.7 this means the electrons are NOT SHARED at all meaning what type of bond is occuring
this means an ionic bond is formed
what must all isomers contain?
they all must contain the SAME molecular formula
what are wave functions?
provides information that allows us to assign a numerical value for each 3-D space relative to the nucleus
what is an orbital?
its a region of space that can be occupied by an electron
how are orbitals defined?
by electron clouds that have specific shapes and sizes
what is an occupied orbital called?
it is called am atomic orbital
what is an atomic orbital?
its a region of space defined with respect to the nucleus of a single atom (ex: s,p,d,f)
describe what a P orbital looks like
a p orbital has 2 lobes- the top lobe has positive values of wave function and the bottom lobe has negative values of wave function
between the lobe is where wave function = 0 which is a node
when are electrons lowest in energy?
when they occupy a 1s orbital b/c the 1s orbital is closest to the nucleus and has no nodes
the more nodes an orbital has the higher the energy or lower the energy it will contain?
higher the energy
what are degenerate orbitals?
they are orbitals with the same energy level
what is the order in which orbitals are filled by electrons?
- aufbau principle- the lowest energy orbital is filled first
- Pauli exclusion principle- each orbital can have a max of 2 electrons & must have opposite spin
- hunds rule- one electron is placed in each degenerate orbital first before electrons are paired up
how is a covalent bond formed?
from the overlap of atomic orbitals
when atomic orbitals overlap they can interfere constructively. what is constructive interference?
constructive interference produces a wave w/ a larger amplitude
when atomic orbitals overlap they can interfere destructively. what is a destructive interference?
it results in waves cancelling each other which produces a node
what is valence bond theory?
the sharing of electrons that are associated with individual atoms, rather than being associated with the entire molecule.
what is the molecule orbital theory?
allows us to explore the consequences of atomic orbital overlap using mathematics
