Alkanes

Question 0

C1H4- C4H10 are :
C5H12- C16H34 are :
Longer chain compounds are ?

Answer 0

Gases
Liquids
Waxes and harder solids

Question 1

Compounds consisting of Only carbon and hydrogen atoms follow what formula ?

Answer 1

CnH(2n+2)

Question 2

Which has a higher boiling/ melting point? Straight chain or a branched isomer?

Answer 2

Straight chain

Question 3

Nucleophile characteristics ?

Answer 3

Normally negatively charges
Nucleus loving 
Attracted to positive charge 
Stronger the base, stronger the Nucleophile 
Act as electron donors

Question 4

Order of nucleophiles in regards to strength ? (Basicity)

Answer 4

RO-, HO-, RCO2-, ROH, H2O

Question 5

Solvent that is able to form hydrogen bonds

Answer 5

Protic solvent

Question 6

In a Protic solvent, the ____ the atom , the better the Nucleophile.

Order of Nucleophile strength?

Answer 6

Larger

CN-, I-, RO-, HO-, Br-, Cl-, F-, H2O

Question 7

In an aprotic solvent, the nucleophiles are naked and thus Nucleophiles are based solely on _______

Order of the halogens for this?

Answer 7

Basicity

Fl-, Cl-, Br-, I-,

Question 8

The best leaving groups are _____ bases

Order of halogens for leaving groups ?

Answer 8

Weak

I, Br, Cl, F

Question 9

Rate of the reaction is dependent on only one molecule, the _____. What is this called ?

Answer 9

Carbocations

Uni molecular nucleophilic substitution

Question 10

Explain the sn1 mechanism

Answer 10

Rds: lg leaves, carbocation forms

Step 2: Nucleophile attacks carbocation

Question 11

Sn1:
Substrate reactivity :
Leaving group:
Nucleophile:

Answer 11

Tertiary-> methyl
Cl Br I weak bases, OH if protonated
Any Nucleophile

Question 12

Sn1:
Solvent ?
Reaction mechanism?
Rate law? 
Stereochemistry?

Answer 12

Polar Protic
2 steps
1st order, r=k(substrate)
Chiral –> racemic mix

Question 13

Sn2
Substrate reactivity ?
Leaving group ?
Nucleophile ?

Answer 13

Methyl –> tertiary
Cl Br I, weak bases
Strong charged Nucleophile

Question 14

Sn2: 
Solvent ?
Reaction mechanism ?
Rate law?
Stereochemistry ?

Answer 14

Polar aprotic
Concerted 1 step
R=k(substrate)(Nucleophile)
Inversion of S/R

Question 15

2 reasons why polar Protic solvents work best for Sn1?

Answer 15

Solvated carbocation intermediate

Form h bonds with leaving group

Question 16

The transition state of the Sn2 forms what ?

Answer 16

Trigonal bipyramidal transition state

Question 17

Typical polar Protic solvents?

Polar aprotic?

Answer 17

Water, alcohol

Acetone, DMSO

Question 18

3 steps for a free radical substitution mechanism?

Answer 18

Initiation: diatomic halogens are cleaved by UV or peroxide forming free radicals
Propagation: radicals produce other radicals continuing the reaction
Termination: two free radicals combine to form a stable molecule

Question 19

Bromine radicals tend to attack __ Alkanes vs chlorine which ___

Answer 19

Tertiary( very selective )

Depends on the stability of the intermediate and on the number of hydrogens present ( more likely to replace primary hydrogens) and react indiscriminately

Question 20

Combustion reactions form ?

Answer 20

CO2, water and heat

Question 21

When a molecule is broken down by heat in the absence of oxygen

Answer 21

Pyrolysis or cracking

Question 22

Function of pyrolysis ?

Answer 22

Reduces avg molecular weight of heavy oils and increases the production of more desirable volatile compounds