2.2 - Polymers, NanoS and Exo/Endo

Question 1

What do the properties of polymers depend on?

Answer 1

The monomers and the conditions used to carry out the reaction

Question 2

Difference between low and high density polymers

Answer 2

High density has higher softening temperature and is stronger than low density

Question 3

What is a thermosoftening polymer?

Answer 3

Consists of individual tangled polymer chains
When heated intermolecular forces become weak and it softens
It can harden when cool
Therefore it can be remolded

Question 4

What is a thermosetting polymer?

Answer 4

Consists of polymer chains with cross links

When heated it doesn’t melt or soften as the bonds are strong

Question 5

What is the scale of Nanoscience?

Answer 5

1-100nm in size

Question 6

Properties of Nanotechnology?

Answer 6

High surface area to volume ratio
Reacts quickly
Strong but light

Question 7

Examples of what nanotechnology is used in?

Answer 7

Catalysts
Sensors detecting substances in small amounts
Coatings
Suncream
Deodorants
Cosmetics

Tennis racket & electrical circuit

Question 8

What is an Exothermic reaction?

Answer 8

Reactions that transfer energy to the surroundings

Question 9

What is an Endothermic reaction?

Answer 9

Reactions that take energy from the surroundings

Question 10

In exothermic reactions does the reaction lose or gain energy from the reactants to the products?

Answer 10

Lose

Question 11

In endothermic reactions does the reaction lose or gain energy from the reactants to the products?

Answer 11

Gain

Question 12

Examples of Exothermic reactions?

Answer 12

Combustion
Oxidation
Neutralisation

Question 13

Examples of Endothermic reactions?

Answer 13

Thermal Decomposition
Photosynthesis
Cooking food

Question 14

If a reversible reaction is exo one way and endo the other what is the energy transferred?

Answer 14

It is the same each way