Exam 1

Question 1

Definition of Polymers

Answer 1

Large macromolecules which are made of many repeating units of smaller molecules.

Question 2

Types of polymers

Answer 2

• Addition polymers
• Condensation polymers
• Polyamides

Question 3

Definition of Addition polymers

Answer 3

monomers’ double bonds are broken and the molecules form a long chain

Ex- polyethylene, polyvinyl chloride, polystyrene.

Question 4

Def of Condensation polymers

Answer 4

Bifunctional monomers react to form a long-chain polymeric molecule

Ex- Nylons, polyesters, polysaccharides.

Question 5

def of Polyamides

Answer 5

formed when compounds with a COOH functional group react with NH2 group.

Question 6

What does the number after nylon mean?

Answer 6

The number of carbon atoms present in each of the original reactants.

Question 7

What technique was used to prepare Nylon in the lab?

Answer 7

Interfacial Polymerization (reaction occurs at the interface of two solutions)

Question 8

Why was sebacoyl chloride used instead of carboxylic acid in the nylon reaction?

Answer 8

Acid chlorides are much more reactive than acids are

Question 9

Why is NaOH used in the Nylon Reaction?

Answer 9

It is used to neutralize the HCl byproduct of the reaction

Question 10

Why are plasticizers added to polymers?

Answer 10

They help to improve the flexibility and extensibility of the polymer

Question 11

Chemiluminescence Definition

Answer 11

The emission of light as the result of a chemical reaction

Question 12

What is the name of the chemical responsible for firefly light?

Answer 12

Luciferase

Question 13

What is the chemical responsible for producing light in a glow stick?

Answer 13

Luminol and Oxalate reactions

Question 14

Practical uses of compounds with chemiluminescent properties

Answer 14

• Forensic science
• Spectroscopy
• Medical diagnosis

Question 15

Diene Definition

Answer 15

unsaturated hydrocarbon containing two double bonds. Must be conjugated and in s-cis- conformation.

Question 16

Dienophile Def

Answer 16

An alkene or Alkyne that readily reacts with a diene.

Question 17

Adduct Def

Answer 17

The product of the diels alder reaction incorporating the reactants

Question 18

What is the thermometer reading during the collection of cyclopentadiene?

Answer 18

41 C

Question 19

Why is cyclopentadiene prepared right before using it?

Answer 19

If stored at room temperature, it is completely converted into the dimer.

Question 20

How was cyclopentadiene added to the solution of Maleic anhydride?

Answer 20

It was added using a dropper while the anhydride was in an ice bath

Question 21

Why was Cyclopentadiene added slowly to maleic anhydride?

Answer 21

The reaction is exothermic and overheating with splashing will occur if the cyclopentadienyl is added too fast.

Question 22

Why was a mixture of solvents used in the DA rxn?

Answer 22

To maintain thermal equilibrium so the adduct will form

Question 23

Why is the nitration of methyl benzoate performed at a low temp?

Answer 23

Temp must be kept below 15 C to prevent the formation of byproducts.

Question 24

How was the filtrate neutralized?

Answer 24

The filtrate is poured into 30 ml of water and 8g of Sodium carbonate is added

Question 25

The main product of nitration of methyl Benzoate

Answer 25

The reaction is regioselective, Methyl 3-nitrobenzoate

Question 26

What are some possible side products of Nitration if the temp is not kept low?

Answer 26

The methyl 3,5 Dinitrobenzoate product

Question 27

Why is the yield of the nitration reaction low?

Answer 27

multiple vacuum filtrations