Using Resources

Question 1

What is meant by a material’s strength?

Answer 1

The resistance of a material to an applied force

Question 2

How are ceramics made?

Answer 2

Shaping and then firing a non-metallic material, such as clay, at a high temperature.

Question 2

Types of clay ceramics are?

Answer 2

Brick, china and porcelain.

Question 3

What does it mean for a material to be brittle?

Answer 3

It will snap easily

Question 3

What are ceramics?

Answer 3

A group of hard, brittle, heat-resistant and corrosion-resistant materials

Question 3

What are the two main types of ceramics?

Answer 3

Clay ceramics and glass

Question 4

What is the type of glass we mostly use?

Answer 4

Soda-lime glass

Question 4

How is soda-lime glass made?

Answer 4

by melting a mixture of sand (silicon oxide), sodium carbonate, and limestone, then allowing the molten liquid to cool and solidify.

Question 5

Why can clay ceramics be used for building?

Answer 5

They have a high compressive strength

Question 6

How is borosilicate glass made and how is it different from soda-lime?

Answer 6

Borosilicate glass is made by heating sand with boron trioxide. Borosilicate glass has a much higher melting point than soda-lime glass.

Question 7

What is a composite material?

Answer 7

A composite material consists of two or more materials with different properties, that have been combined to produce a material with more desirable properties.

Question 8

What are the two components making up most composites.

Answer 8

The reinforcement and the matrix

Question 9

What is the reinforcement of a composite?

Answer 9

It is often long solid fibres or fragments.

Question 10

What is the matrix of a composite?

Answer 10

Usually something that is soft, then hardens - it binds the reinforcement together.

Question 11

What are polymers?

Answer 11

Polymers re large molecules of high relative molecular mass, made by linking together lots of smaller molecules called monomers

Question 12

What to the properties of a polymer depend on?

Answer 12

the monomers from which it was made and the conditions of the chemical reaction.

Question 13

Generally, polymers have properties such as?

Answer 13

flexible, easily shaped, and good insulators of heat and electricity.

Question 14

What are the two main types of poly(ethene)?

Answer 14

Low-density (LDPE) and high-density (HDPE)

Question 15

Structure of LDPE

Answer 15

Low density branched chains which prevent tight packing

Question 16

Structure of HDPE

Answer 16

High density straight chains which allow for tight packing.

Question 17

Bonding and forces of LDPE

Answer 17

Weak intermolecular forces

Question 18

Bonding and forces of HDPE

Answer 18

Strong intermolecular forces

Question 19

Formation of LDPE

Answer 19

Moderate temperatures, high pressure and trace of oxygen (catalyst)

Question 20

Formation of HDPE

Answer 20

Lower temperatures/pressure, and a catalyst at 50 degrees c

Question 21

Properties of LDPE

Answer 21

Weaker structure, flexible with low melting points

Question 22

Properties of HDPE

Answer 22

Stronger structure, rigid with high melting points

Question 23

Thermosoftening polymers are?

Answer 23

• Made from lots of polymer chains held together by weak intermolecular forces
• The weak intermolecular forces break easily when heated, melting the polymer
• They can be remoulded into a different shape and will harden when cooled

Question 25

Thermosetting polymers are?

Answer 25

-Made from lots of polymer chains, held together by strong covalent bonds
- These covalent bonds require a lot of energy to break, so don’t soften when heated
- These polymers are hard, strong, and rigid.

Question 26

Structure of thermosoftening polymers

Answer 26

Long straight chains that are tangled up

Question 27

Structure of thermosetting polymers

Answer 27

Rigid structure with fixed chains

Question 28

What is the key difference between metals and alloys

Answer 28

Alloys are malleable