Hybridisation in Carbohydrates
Causes the system to become more stable, in carbon the 2s 2p --> 4sp3
An electron is taken from the 2s shell and promoted to the px,py,pz (small energy gap), this provides 4 lone pairs of electrons for bonding.
The carbon atom is in an 'excited state'
The 4 bonds of equal energy provide a tetrahedron shape.
Isomers of Alkanes
Constitutional (1) - same molecular formula, different carbon skeleton
Constitutional (2) - same carbon skeleton, different double bond position
Geometric - same carbon skeleton and double bond position, different order around the double bond ( due to no free rotation around a d. bond)
Cis or Trans.
Non superimposable mirror images
Enantiomers (non superimposable)
Bonds to chiral carbons drawn as intersecting lines with the chiral carbon at the the center
Horizontal = bonds that come forward
Vertical = Bonds that point away
Most highly oxidised carbon at top.