5. Transition Metals, Nanoparticles and Materials

Question 1

What are the properties of transition metals?

Answer 1

High melting and boiling points;
sonorous (ring when struck), lustrous (shiny)
multiple oxidation states;
produce coloured compounds;
are used as catalysts;
Relatively unreactive (i.e. with water, oxygen and halogens);
hard, strong, dense;
malleable/ductile;
good electrical/thermal conductors

Question 2

What is the symbol for manganese?

Answer 2

Mn

Question 3

What is the symbol for titanium?

Answer 3

Ti

Question 4

What is the symbol for chromium

Answer 4

Cr

Question 5

What properties do group 1 metals and transition metals have in common?

Answer 5

sonorous (ring when struck), lustrous (shiny)
malleable/ductile;
good electrical/thermal conductors

Question 6

What properties do transition metals have that group 1 metals do not have?

Answer 6

High melting and boiling points;
multiple oxidation states;
produce coloured compounds;
are used as catalysts;
Relatively unreactive (i.e. with water, oxygen and halogens)
hard, strong, dense;

Question 7

What are the three classifications of particulate matter?

Answer 7

coarse or dust
fine
nanoparticle

Question 8

What is the size (diameter) range of a nanoparticle?

Answer 8

1 - 100 nm

Question 9

What is the approximate number of atoms in a nanoparticle?

Answer 9

500

Question 10

What is the size of an atom?

Answer 10

0.1 nm

Question 11

What are the risks associated with coarse or dust particles?

Answer 11

They can be inhaled and get stuck in our lungs.

Question 12

What are the risks associated with fine particles?

Answer 12

They are small enough to get into our blood stream.

Question 13

What is the relationship between the size of a particle and its surface area to volume ratio?

Answer 13

They are inversely proportional. If the size doubles the surface area to volume ratio halves.

Question 14

What is the size (diameter) range of a fine particle?

Answer 14

100 nm - 2500 nm

Question 15

What is the size (diameter) range of a dust or coarse particle?

Answer 15

1 x 10-5 m and 2.5 x 10-6 m

Question 16

What are the uses of nanoparticles?

Answer 16

Catalysts
Medicine delivery
Fabrics
Cosmetics
Electronics

Question 17

What are some of the potential dangers associated with nanoparticles?

Answer 17

Can get into the blood stream

Can accumulate in the environment with unknown consequences

Question 18

What is soda-lime glass made from?

Answer 18

sand, sodium carbonate and limestone

Question 19

What is borosilicate glass made from?

Answer 19

sand and boron trioxide

Question 20

What is the benefit of borosilicate glass?

Answer 20

It melts at a higher temperature.

Question 21

What do we make from clay ceramics?

Answer 21

Pottery and bricks

Question 22

How do we make things from ceramics?

Answer 22

shaping wet clay and then heating in a furnace

Question 23

Name the two main constituents of a composite.

Answer 23

The matrix and the binder

Question 24

Give some examples of composite materials

Answer 24

Fibreglass
Carbon fibre
Concrete
Wood

Question 25

What are the properties of ceramics?

Answer 25

Can be moulded when wet (for clay) or hot (for glass)
Hard, brittle once dried (for clay) or cooled (for glass)
Glass is also often transparent

Question 26

What are properties of composites?

Answer 26

Strong
Low density
so high strength to weight ratio

Question 27

How are polymers made?

Answer 27

Combining monomers (often coming from oil) in specific temperatures and conditions.

Question 28

What are the properties of polymers?

Answer 28

Strong
Low density
so high strength to weight ratio
often transparent

Question 29

What are the two types of polymer?

Answer 29

Thermosoftneing

Thermosetting

Question 30

What are the properties of thermosoftneing plastics?

Answer 30

They consist long polymer chains twisted, but not bonded together. There are weak forces between the chains
They will melt and can be remoulded on heating.
They are often more flexible than thermosetting polymers.

Question 31

What are the properties of thermosetting plastics?

Answer 31

They consist long polymer chains with crosslinking and so strong covalent bonds between the chains.
They will burn on reheating.
They are strong, hard and rigid.