bulk and surface properties of matter (topic 2) Flashcards
1
Q
suggest why nanoparticles are needed in only very small amounts
A
they have a high surface area to volume ratio
2
Q
- in certain areas of the UK, tap water contains aluminium ions
- what would you see when sodium hydroxide solution is added drop by drop to tap water containing aluminium ions (2)
A
- (sodium hydroxide) produces a white precipitate
- which (then) dissolves (in excess sodium hydroxide)
3
Q
A
hundred
4
Q
diamond has a giant: covalent, ionic or metallic structure
A
covalent
5
Q
suggest two ways in which using ‘nanocoated’ tennis balls would be good for the environment
A
- less materials, save resources
- less energy
- less pollution
- less waste
6
Q
explain how a catalyst increases the rate of a reaction (2)
A
- a catalyst provides an alternative reaction route
- that has lower activation energy
7
Q
A
79
79
8
Q
how does a catalyst help a reaction (1)
A
- changes rate of reaction
- speeds up or slows down reaction
9
Q
(1)
A
crosslinking
10
Q
A
- each atom is joined to four other atoms
- it has a giant structure
11
Q
suggest why silver stops unpleasant smells when wearing the socks (1)
A
kills bacteria
12
Q
suggest why the silver nanoparticles are more effective at preventing unpleasant smells than normal sized silver particles (1)
A
- larger surface area
- react faster
