Chapter 18-Polymers (Organic Chemistry cont.)

Question 1

Define:

polymers.

Answer 1

A substance containing large molecules (large molecules) made from lots of small molecules (monomers) joined together.

Remember: poly means many

Question 2

What is polymerisation**?

Answer 2

Is a reaction, where thousands of monomers join together to form polymers.

Question 3

Why can’t alkanes undergo polymerisation?

Answer 3

Because they have no spare bonds as they are saturated.

Question 4

List the reaction conditions.

Answer 4

1. Heat
2. High Pressure
3. Catalyst (Titanium/Aluminum compound)

Question 5

State the two polymerisation reactions.

Answer 5

1. Additional polymerisation
2. Condensation polymerisation

Question 6

How does additional polymerisation happen?

Answer 6

• Alkenes (between the same monomers)
• Double bond opens uo
• All the molecules join together form a macromolecule
• Consists of thousands of molecules joined up.

Question 7

List 3 of the uses of the following polymers:

1. Polythene
2. Polychloroethen (PVC)
3. Polypropene
4. Polysterene
5. Teflon

Answer 7

1. Plastics: bag, bins, bottles
2. Water pipes, hoses, clothing
3. Crates, ropes
4. Fast food cartons, insulation on roofs and walls
5. Coating on frying pans, fabric protector, flooring.

Question 8

What makes condensation polymerisation different from additional polymerisation?

Answer 8

1. Two different monomers join
2. Each has two functional groups that take part in the reaction.
3. The monomers joins at their functional groups, by getting rid of or eliminating small molecules.

Question 9

How is nylon made?

Answer 9

• No double bonds break. Instead, single bond break and new single bonds form.
• Monomers are able to join to each other by eliminating a small molecue. (In this example, hydrogen chloride)
• This reaction continues at each two monomers.
• Thousands of monomers join together, giving a macromolecule.

Question 10

How is terylene made?

Answer 10

• The monomers join by eliminating water

Question 11

What does the amide linkage consist of, and what does the ester linkage?

Answer 11

1. Amide linkage (CHON) Note: amide linkage in proteins.
2. Ester linkage (COO) Note: ester linkage in fats.

Question 12

List some of the problems with plastics/polymers.

Answer 12

• Non-biodegradable- Do no naturally decompose. They are around for millions of years.
• Stays in rivers/sea and can be fatal for marine life
• Can kill animals when they’re ingested
• Block drains and sewers
• Give off toxic fumes when burned

Question 13

What’s the reactants for the following macromolecules after hydrolysis:

1. Fats
2. Starch
3. Proteins

Answer 13

1. Fats > Fatty Acids + Glycerol
2. Starch > Glucose
3. Proteins > Amino Acids

Question 14

The hydrolysis of proteins results in amide linkage, the hydrolysis of fats is ester linkage…

What’s the hydrolysis of starch to glucose?

Question 15

When hydrolysis is incomplete not all he macromolecules get broken down, this results in a mixture of molecules.

How would you tell them apart.

Answer 15

• Chromotography
• However, amino acids & sugars are colourless-so a locating agent must be used.
• Using R_f values, one can tell what the different molecules are from the mixture.

(_Remember: _ R_f = Distance travlled by solute / Distance travlled by solvent)

Question 16

Describe the condensation reaction from glucose to starch.

Answer 16