Module 3: Introduction to Reaction Mechanisms

Question 1

unequally divide electrons

Answer 1

heterolysis or heterolytic cleavage

Question 2

Electrons move from a nucleophilic source (Nu: or Nu:+) to an?

Answer 2

electrophilic site

Question 3

These are nucleophiles because they contain a carbon with a lone pair

Answer 3

carbanions

Question 4

The stronger the bond, the ________ its bond dissociation energy

Answer 4

higher

Question 5

This reaction occur when two reactants add together to form a single product with no atoms “left over.”

Answer 5

addition reaction

Question 6

bond breaking is?

Answer 6

endothermic

Question 7

Indicate breaking and forming of bonds using an?

Answer 7

arrowhead

Question 8

This is the energy needed to homolytically cleave a covalent bond.

Answer 8

bond dissociation energy

Question 9

This involves only one step the starting material is directly converted to a product no matter how many bonds are broken or formed

Answer 9

One-step/concerted reaction

Question 10

it describes reaction rates

Answer 10

kinetics

Question 11

This involves more than one step the starting material is first converted to an unstable intermediate then goes on to form the product

Answer 11

Stepwise reaction

Question 12

different kinds of reactions that do exist

Answer 12

1. addition reaction
2. elimination reaction
3. substitution reaction
4. rearrangement reaction

Question 13

this if broken in addition reactions

Answer 13

pi bond

Question 14

These are electrophiles because they contain an electron-deficient carbon

Answer 14

radicals and carbocations

Question 15

This reaction occurs when two reactants exchange parts to give two new products

Answer 15

substitution reaction

Question 16

equally divide electrons

Answer 16

homolysis or homolytic cleavage

Question 17

It is unstable and can’t be isolated, but we can nevertheless imagine it to be an activated complex of the two reactants

Answer 17

transition state

Question 18

It is formed in elimination reactions

Answer 18

pi bond

Question 19

These reactions are exactly opposite

Answer 19

addition and elimination reactions

Question 20

this represents the highest-energy structure involved in this step of the reaction

Answer 20

transition state

Question 21

The nucleophile can be either?

Answer 21

negatively charged or neutral

Question 22

bond making is?

Answer 22

exothermic

Question 23

This is the overall description of how a reaction occur

Answer 23

reaction mechanism

Question 24

This accounts for all reactants used and all products formed.

Answer 24

complete mechanism

Question 25

the bigger the size of the halogen, the _____________ is the bond strength

Answer 25

lower

Question 26

This reaction occurs when a single reactant splits into two products, often with formation of a small molecule such as water or HX .

Answer 26

elimination reaction

Question 27

This indicates homolytic and homogenic steps forming radicals

Answer 27

“half” head (“fish-hook”)

Question 28

is describes energy and equilibrium

Answer 28

thermodynamics

Question 29

This indicates heterolytic and heterogenic steps forming ions

Answer 29

Complete head

Question 30

Organic chemical reactions can be organized broadly in two ways:

Answer 30

WHAT kinds of reactions occur
HOW those reactions occur

Question 31

This reaction is, in a sense, the opposite of addition reaction.

Answer 31

elimination reaction

Question 32

For a reaction to take place, these must collide and reorganization of atoms and bonds must occur.

Answer 32

reaction molecules

Question 33

Two ways of breaking or forming a bond:

Answer 33

1. homolysis or homolytic cleavage
2. heterolysis or heterolytic cleavage

Question 34

The reactivity of organic molecules is influenced by two main factors:

Answer 34

1. Electron-deficient sites
2. Electron-rich site

Question 35

it is the energy difference between reactants and transition state and determines how rapidly the reaction occurs at a given temperature

Answer 35

activation

Question 36

The electrophile can be either?

Answer 36

positively charged or neutral

Question 37

Atoms are rearranged resulting in the formation of a new substance or substances.

Answer 37

rearranged reaction