Carbon compounds and isomerism

Question 1

What does IUPAC stand for?

Answer 1

International union of pure and applied chemistry

Question 2

General formula of alkanes

Answer 2

CnH2n+2

Question 3

What happens to mp and bp if number of carbons in an alkane increases?

Answer 3

Increases

Question 4

What are the two determinants for strength of dispersion force?

Answer 4

1. number of electrons surrounding molecule

2. surface area of molecule

Question 5

General formula of an alkyl

Answer 5

CnH2n+1

Question 6

What is the unique feature of alkyls?

Answer 6

They are univalent radicals/ lack of 1 hydrogen

Question 7

What is an aryl?

Answer 7

Any functional group derived from a simple aromatic ring

Question 8

General formula for alkenes

Answer 8

CnH2n

Question 9

General formula for alkynes

Answer 9

CnH2n-2

Question 10

What is unique about alkynes?

Answer 10

They contain at least one triple bond.

Question 11

Describe cis/trans-isomerism

Answer 11

A type of stereoisomerism, which describes the orientation of functional groups within a molecule.

Question 12

How can you identify whether it is cis or trans?

Answer 12

cis- functional groups on the same side

trans- functional groups on opposite sides

Question 13

What is structural isomerism?

Answer 13

same general formula but different structure/arrangment

Question 14

What is enantiomeric isomerism and what is another name for it?

Answer 14

Molecules that are non-superimposable mirror images of each other (must have a chiral carbon) . Optical isomerism

Question 15

What notation do we use for enantiomeric isomerism?

Answer 15

+/- or D/L or Cahn Ingold Prelog (R/S)
+/D for sugars
-/L for amino acids

Question 16

How do we use the Cahn Ingold Prelog?

Answer 16

1. identify chiral centre
2. Assign priority depending on atomic number
3. position lowest priority group away
4. look at the other 3 groups and determine direction of high to low priority
5. If clockwise then its R and if anticlockwise then its S

Question 17

What are tautomers?

Answer 17

Molecules with the same molecular formula but different connectivity