Alkanes , Cycloalkanes and Alkyl Halides

Question 1

Saturated Hydrocarbons

Answer 1

Only hydrogens and sp3 hybridised carbons

Question 2

n-alkanes

Answer 2

Chains of -CH2- groups (methylene groups),

Question 3

Branched alkanes

Answer 3

Structural isomers of n-alkanes

Question 4

equation for hydrogens in carbon atoms

Answer 4

(2n + 2) hydrogen atoms

Question 5

Non-polar molecules

Answer 5

Dissolve in non-polar or weakly polar organic solvents and are hydrophobic
Less dense than water and insoluble in water

Question 6

Which bond does rotation occour?

Answer 6

In single bonds not double

Question 7

Conformational isomer

Answer 7

• Formed due to rotation of carbon sp3

Question 8

What energy conformation are structures usually drawn in?

Answer 8

• Lowest-energy conformation: the one with
  minimal electrostatic repulsion between bonds
• Bonds are usually 120 degrees appart (Rotation at 120)
• Stable conformation

Question 9

High energy conformation

Answer 9

• Rotation at 60 degrees
• Looking at newmans projection the front hydrogens and inm the same plane as back 9eclipse and repel at first rotation
• Torsional strain

Question 10

what energy does the staggered formation have

Answer 10

• Lowest relative energy at angle 60 280 and 300 dihedral angle

Question 11

Gauche

Answer 11

• 1st staggered level it is synclinical
• 2 biggest substituent next to each other

Question 12

Opposed

Answer 12

• No eclipses are with large molecules

Question 13

Cycloalkane

Answer 13

• open-chain alkanes in their physical properties
  and in their chemistry

Question 14

Cis

Answer 14

Two substituents point toward the same face

Question 15

trans

Answer 15

Two substituents point toward opposite face

Question 16

Torsional strain

Answer 16

• Chair conformation is required due to strain not flat but staggered
• 109.5 degree angle

Question 17

Cyclohexane conformational equalibria chair

Answer 17

• Lowest energy all hydryogen as far appart as posible to avoid tortional strain

Question 18

Chain formation structure

Answer 18

Axial substituentdrawn vertically
Equatorial drawn parallel to the next but-one C-C bond

Question 19

Does cyclohexane prefer equatorial or axial

Answer 19

• Prefer to stay in equatorial less interaction between substituents

Question 20

Larger substituents give a greater preference to

Answer 20

• Equatorial position

Question 21

Alkyl halides

Answer 21

Halogen atom bonded to one of the sp3 hybrid atoms

Question 22

Vinyl halide

Answer 22

Halide bonded from carbon double bond

Question 23

Aryl halide

Answer 23

• Benzene with halide bonded

Question 24

Nucleophiles

Answer 24

• Wish to form bonds by donating or sharing their electrons
• electrons rich and can be negative ions, or neutral molecules with electron lone pairs

Question 25

Electrophiles

Answer 25

• Wish to form bonds by accepting electrons or
  sharing electrons with a reactant molecule
  electron deficient and can be positive ions or neutral (but δ+) molecules

Question 26

Nucleophilic substitution

Answer 26

• Replaces a leaving group (X−) from a
  carbon atom, using its lone pair of electrons to form a new bond to the carbon atom

Question 27

Elimination reaction

Answer 27

• Halide ion leaves along with another atom or ion (often H+), a
  new pi bond results. Dehydrohalogenations (H-X). Reagent (B:-) reacts as a base.
• Most nucleophiles are also basic

Question 28

Where do the curly arrows go

Answer 28

• Nucleophil eto electrophile
• movement of electrons