Block 1: Fundamentals Flashcards
What are sp3 hybridised orbitals? What bonds do they form?
1x 2s orbital combined with 3x 2p orbitals to form 4 equal sp orbitals. They form sigma bonds with each other
What are sp2 hybridised orbitals? What bonds do they form?
1x 2s orbital combined wit 2x 2p orbitals to form 3 sp orbitals and one unhybridised p orbital. The hybridised orbitals form sigma bonds, while the p orbital can overlap with other p orbitals to form a weaker double bonda
What are sp hybridised orbitals? What bonds do they form?
1x 2s orbital combined wit 1x 2p orbital to form 2 sp orbitals and two unhybridised p orbitals. The hybridised orbitals form sigma bonds, while the p orbitals can overlap with other p orbitals to form two weaker bonds (triple bond).
What is electronegativity?
A measure of the ability of a bonded atom to attract electrons to itself
How does chromatography work?
There is a polar and non polar phase. As the non polar phase moves up the polar phase (with the solutes on it), the non polar solutes are less attracted to the polar phase and move quickly with the non polar phase. The polar solutes are more attracted and don’t move as much. Therefore the components can be separated.
What is a functional group?
A recognizable arrangement of atoms that is characteristic of a class of molecules. Compounds containing the same functional group can be expected to display similar reactivity.
What are CH2OH side chains called?
Methoxy groups
What is unique about benzene?
It is a resonance hybrid- all p electrons are shared across the structure in pi bonds. It does not undergo typical ‘alkene’ reactions
What is a ring with the functional groups on adjacent carbons?
Ortho
What is a ring with the functional groups separated by one Carbon?
Meta
What is a ring with the functional groups on opposite carbons?
Para
What are constitutional isomers?
Same molecular formula, different sequence of bonds
What are stereoisomers?
Same molecular formula, different arrangement of atoms in space
What are conformational isomers?
A type of stereoisomer which differ by rotation around a single bond
What are configurational isomers?
A type of stereoisomer where interconversion requires breaking bonds
What are enantiomers?
A type of configurational isomer where isomers are non superimposable mirror images
What are diasteriomers?
A type of configurational isomer where isomers are not mirror images
What is the equation to calculate DBEs?
1/2(2n4 + n3+ - n1 +2)
What are the different ns in the DBE equation?
n4= C n3= N n1= H/X
What is the sawhorse projection?
Views bonds of two carbons from an oblique angle across the c-c bond
What is the newman projection?
Front-on view of the c-c bond, where middle dot is front carbon and large circle is back carbon
What is the most stable conformer?
Large groups opposite with atoms staggered (anti configuration)
What is the gauche conformer?
Bonds staggered but two large groups of each carbon are adjacent
What is the least stable conformer
Large groups on top of one another, atom eclipsed.
What are the two cyclohexane conformer shapes and which is more stable?
Chair and boat. Chair is the most stable.
How do you make substituted cyclohexanes more stable?
Large groups located in equilateral bonding positions. (Each C has two bonds, one axial and one equilateral).
What are cis/trans isomers used for?
Disubstituted rings. Both equi/axial = cis, one of each = trans
What are E/Z isomers?
If high priority (larger mass) groups are on the same side of the double bond, = z isomer. If on different sides = E isomer.
What are R/S isomers?
Different arrangements of enantiomers. With the lowest priority (mass) group going into back of page, if progression of next groups from highest to lowest priority runs clockwise, R. If anticlockwise, S.
