This question is about particles.
Put the following particles in order of size starting with the smallest.
Coarse particles Nanoparticles Fine particles
Smallest: ___________________
___________________
Largest: ___________________
How does the size of a nanoparticle compare to other types of particle?
Give two uses of nanoparticles.
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This question is about the properties of nanoparticles.
What are nanoparticles?
2 marksFigure 1 shows a nanoparticle of silver.
Each side of the nanoparticle has a length of 20 nm.
Calculate the volume and surface area of the nanoparticle.
Silver nanoparticles are added to the fibres used to make some socks as they prevent unpleasant smells.
Suggest why silver nanoparticles prevent unpleasant smells.
Tick (
) one box.
| They provide colour to the socks | |
| They kill bacteria | |
| They make the sock feel softer |
Why are normal sized particles not as effective at doing this job compared to nanoparticles?
3 marksAn atom of silver is represented as:
Calculate the number of protons, neutrons and electrons in an atom of silver.
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This question is about nanoscience.
Draw one line from each particle to the correct size.
Why are nanoparticles effective even when used in very small quantities?
Tick (✔) one box.
| They are reactive compounds | |
| They have a high surface area to volume ratio | |
| They have a low boiling point | |
| They can adopt different shapes |
State one advantage of using nanoparticles in sun lotions.
State one disadvantage of using nanoparticles in sun lotions.
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This question is about nanoparticles and carbon nanotubes.
The structure of a carbon nanotube is shown in Figure 1.
|
Nanoparticles contain a few |
|
atoms. |
One use of carbon nanotubes is as catalysts.
Explain how a catalyst increases the rate of a reaction.
One use of carbon nanotubes is as catalysts.
Give two other uses of carbon nanotubes.
Complete the sentences to describe and explain the properties of carbon nanotubes.
Carbon nanotubes have ____________________ melting points because of strong ____________________ bonds.
They can conduct electricity because ____________________ are free to move throughout the structure.
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This question is about nanoparticles of iron oxide.
Small amounts of iron oxide are added to river water to kill toxic substances.
Complete the sentence.
The size of a nano-sized particle is ____________________ than normal-sized particles.
2 marksA nanoparticle of iron oxide is a cube of side 40 nm.
Figure 1 represents a nanoparticle of iron oxide.
Calculate the volume of the nanoparticle and state the units.
| 120 | 1600 | 9600 | 64 000 |
Volume__________________ Units _____________
Why are less iron oxide nanoparticles needed to have the same effect as the normal sized particles?
Suggest why it is beneficial for the manufacturer to use iron oxide nanoparticles.
Iron oxide has ionic bonds.
The charge on the oxide ion is O2-.
How did oxygen become an oxide ion?
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This question is about nanoparticles in products used for protection against the sun.
|
Sun Screens Nanoparticles of titanium oxide are used in some sun creams. Sun screens that use nanoparticle technology spread more easily and provide better coverage so you use less. They are also transparent unlike traditional screens which are white. Normal sized particles of titanium oxide are safe but nanoparticles of this compound are thought to be absorbed into the body through our skin. Once in the body, they can travel around in our bloodstream unheeded. Some scientists suspect that these nanoparticles may be toxic to some types of cells found in the brain, skin, liver and bones. |
Explain why nanoparticles of titanium oxide are able to pass through the skin and travel around the body more easily than normal-sized particles of the same compound.
Give three reasons why sunscreens containing nanoparticles should be subjected to further testing.
Suggest why some companies that make sun creams might prefer to not engage in further testing.
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Graphene is a single layer of graphite.
It can conduct electricity and can be used in loudspeakers.
Explain why graphene can conduct electricity.
Explain why graphene is strong.
Explain why graphite can be used in the tips of pencils.
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This question is about nanoparticles and their uses.
Nanoparticles of platinum can be used in modern catalytic converters.
Catalytic converters are found in car engines and prevent harmful substances that are produced when petrol burns from being released into the air.
Figure 1 represents a platinum nanoparticle.
All sides are the same length.
Calculate the surface area to volume ratio of this particle.
Give your answer in the simplest whole number ratio.
Burning petrol in a car is an exothermic reaction.
Draw and label the reaction profile for an exothermic reaction in Figure 2.
Include labels for:
Figure 2
Platinum is a transition metal.
Describe the bonding and structure of platinum.
Why is it cheaper to use nanoparticles of platinum as opposed to coarse particles of platinum?
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Processors in computers can be damaged if they are exposed to high levels of heat.
To avoid this a heat sink is placed on top of the processor as shown in Figure 1.
A heat sink is a metal that conducts heat away from the processor.
Explain why the metal is a good conductor of heat.
Heat sinks are often made from copper, a transition metal.
Compare the properties of copper to the Group 1 metal, sodium.
Grease is used to fill the gaps between the processor and the heat sink.
Without the grease, the gaps contain air which is a poor conductor, so the grease improves the transfer of heat from the processor to the sink.
One manufacturer of thermal grease claims that grease containing nanosized particles of silver will help transfer the heat better than if fine particles were used.
How are nanosized particles different from fine particles?
Suggest one reason why fine particles of silver might not transfer heat as well as nanosized particles.
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This question is about silver nanoparticles.
Silver can form cubic nanocrystals as shown in Figure 1 below.
Figure 1
A silver nanocrystal is a cube shaped nanoparticles with each side measuring 20 nm.
Calculate the surface area to volume ratio of the silver nanocrystal.
Silver nanoparticles are sometimes used in clothing to prevent odours.
Suggest why it is more economical to use nanoparticles of silver rather than coarse particles.
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Nanoparticles are useful substances with many applications.
Tick (✔) one use of nanoparticles.
|
In the extraction of zinc |
|
|
In suntan lotions |
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|
In the test for water |
How does the size of nanoparticles compare to normal-sized particles?
Draw a ring around the correct answer.
| much smaller | same size | much larger |
Tiny amounts of cerium oxide nanoparticles can be added to diesel fuel as a catalyst.
Why are only a tiny amount of cerium oxide nanoparticles used?
Explain how nanoparticles are able to catalyse reactions.
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Nanocrystalline metals are a new kind of metal structure which are based on nanoparticle science.
Nanocrystalline metals are much harder and stronger than normal metals and their use in the production of artificial limbs is being investigated.
Crystals in normal metal structures are around 20,000 nm in diameter.
Explain how a metal and nanoparticles of the same metal can have different properties.
In terms of size, how do the crystals in nanocrystalline metals compare with the crystals in normal metals?
Hip joints are constantly moving when people move or walk during normal daily activities.
Suggest and explain why an artificial hip joint made of a nanocrystalline metal should last longer than one made from normal metals.
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Modern catalytic converters use nanosized particles of catalytic metals such as palladium and rhodium.
Using nanosized particles is more cost effective than normal sized particles.
Suggest and explain why the use of nanosized catalyst particles reduces the production costs of catalytic converters.
Nanoparticles of magnesium oxide have antibacterial properties.
Figure 1 below shows the percentage of bacteria killed.
Figure 1
Draw three conclusions from Figure 1.
Not all sizes of nanoparticles have points plotted.
Would including data for more sizes of nanoparticles improve the conclusions that can be drawn about their effect on killing bacteria?
Give a reason for your answer.
A coarse particle has a diameter of 1 × 10−6 m and a nanoparticle has a diameter of 1.6 × 10−9 m.
Calculate how many times larger the diameter of the coarse particle is than that of the nanoparticle.
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This question is about nanoparticles and water.
Hydrogen and oxygen chemically combine to produce water molecules.
What type of bonding is present in a molecule of water.
Does pure water conduct electricity?
Give a reason for your answer.
Nanoparticles of cobalt oxide are used as a catalyst in the production of hydrogen from water.
Compare the size of a nanoparticle with the size of an atom.
Explain why 1g of nanoparticles is a better catalyst than 1g of cobalt oxide powder.
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