Block 1: Fundamentals

Question 1

What are sp3 hybridised orbitals? What bonds do they form?

Answer 1

1x 2s orbital combined with 3x 2p orbitals to form 4 equal sp orbitals. They form sigma bonds with each other

Question 2

What are sp2 hybridised orbitals? What bonds do they form?

Answer 2

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

Question 3

What are sp hybridised orbitals? What bonds do they form?

Answer 3

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).

Question 4

What is electronegativity?

Answer 4

A measure of the ability of a bonded atom to attract electrons to itself

Question 5

How does chromatography work?

Answer 5

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.

Question 6

What is a functional group?

Answer 6

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.

Question 7

What are CH2OH side chains called?

Answer 7

Methoxy groups

Question 8

What is unique about benzene?

Answer 8

It is a resonance hybrid- all p electrons are shared across the structure in pi bonds. It does not undergo typical ‘alkene’ reactions

Question 9

What is a ring with the functional groups on adjacent carbons?

Answer 9

Ortho

Question 10

What is a ring with the functional groups separated by one Carbon?

Answer 10

Meta

Question 11

What is a ring with the functional groups on opposite carbons?

Answer 11

Para

Question 12

What are constitutional isomers?

Answer 12

Same molecular formula, different sequence of bonds

Question 13

What are stereoisomers?

Answer 13

Same molecular formula, different arrangement of atoms in space

Question 14

What are conformational isomers?

Answer 14

A type of stereoisomer which differ by rotation around a single bond

Question 15

What are configurational isomers?

Answer 15

A type of stereoisomer where interconversion requires breaking bonds

Question 16

What are enantiomers?

Answer 16

A type of configurational isomer where isomers are non superimposable mirror images

Question 17

What are diasteriomers?

Answer 17

A type of configurational isomer where isomers are not mirror images

Question 18

What is the equation to calculate DBEs?

Answer 18

1/2(2n4 + n3+ - n1 +2)

Question 19

What are the different ns in the DBE equation?

Answer 19

n4= C
n3= N
n1= H/X

Question 20

What is the sawhorse projection?

Answer 20

Views bonds of two carbons from an oblique angle across the c-c bond

Question 21

What is the newman projection?

Answer 21

Front-on view of the c-c bond, where middle dot is front carbon and large circle is back carbon

Question 22

What is the most stable conformer?

Answer 22

Large groups opposite with atoms staggered (anti configuration)

Question 23

What is the gauche conformer?

Answer 23

Bonds staggered but two large groups of each carbon are adjacent

Question 24

What is the least stable conformer

Answer 24

Large groups on top of one another, atom eclipsed.

Question 25

What are the two cyclohexane conformer shapes and which is more stable?

Answer 25

Chair and boat. Chair is the most stable.

Question 26

How do you make substituted cyclohexanes more stable?

Answer 26

Large groups located in equilateral bonding positions. (Each C has two bonds, one axial and one equilateral).

Question 27

What are cis/trans isomers used for?

Answer 27

Disubstituted rings. Both equi/axial = cis, one of each = trans

Question 28

What are E/Z isomers?

Answer 28

If high priority (larger mass) groups are on the same side of the double bond, = z isomer. If on different sides = E isomer.

Question 29

What are R/S isomers?

Answer 29

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.