structure, bonding and ring systems Flashcards
what makes 4 identical sp3 orbitals
1x2s and 3x2p
what makes 3 identical sp2 orbitals
1x2s and 2x2p , leaving a p orbital unhybridised
how is ethene formed
3 sp2 orbitals and the remaining p orbitals make a pi bond causing the double bond
what makes a sp orbital
1x2s and 1x2p, leaving 2x p orbitals unhybridised
bond rotation is possible around _____ bonds
single
in a staggered conformation, the C are ….
as far away as possible
is the staggered or the escplipsed lower in energy? (more stable) why?
staggered, due to the torsional strain from electron-electron repulsions in adjacent C-H bonds in the eclipsed form
what is a steric effect
non-bonding interactions which cause a change in the shape of a molecule
Me groups have a ____ steric effect which contribute to _____
large, rotational barriers
the mirror images of molecules are …
identical in energy
the interaction of substituents on adjacent carbon atoms in known as ….
steric strain
what is torsional strain
a resistance to bond twisting, occurs in an eclipsed conformation instead of the more stable staggered conformation.
what causes the most steric strain
when 2 groups larger than H are onto of eachother - Newman projection
what is the most favoured conformation for cyclopentane?
envelope
what does puckering do?
reduces torsional strain and angle strain
why is the boat less stable than the chair
then looking from the Newman projection we can see that the carbon bonds are eclipsed which is much less stable
which conformation of cyclohexane is most stable , and therefore lower in energy?
equatorial -
what is 1,3 diaxial interactions ?
steric interactions between an axial substituent located on the 1st carbon atom of a cyclohexane ring and the substituents located on carbon atoms 3 and 5
what is the reason why axial conformation is more destabilised
1,3 diaxial interactions
