AQA GCSE Chemistry Foundation (8462), Foundation tier · Bonding, structure and the properties of matter › Nanoparticles
Practise Uses of nanoparticles. 7 exam-style questions on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
Where nanoparticles are used (medicine, electronics, cosmetics and sun creams, deodorants and catalysts), and the benefits and possible risks of using them. You do not need to learn specific examples: questions give you information and ask you to evaluate a use, often for 4 to 6 marks. GCSE Chemistry only, not in Combined Science.
Key facts
Uses: medicine, electronics, cosmetics and sun creams, deodorants, catalysts
Advantage: high surface area to volume ratio → more effective → smaller quantities needed
Sun creams: better UV protection and better skin coverage
Risks: may get into the body and cells, possible cell damage, possible harm to the environment
Long-term effects are not yet fully understood
Evaluate = benefits + risks + a justified judgement
Notes
Where nanoparticles are used
Medicine: for example, carrying drugs to particular places in the body, or killing bacteria.
Electronics: very small components and conducting materials.
Cosmetics and sun creams: nanoparticles in sun creams give better protection from harmful ultraviolet (UV) light and better skin coverage, and they do not leave white marks on the skin.
Deodorants: for example, nanoparticles that kill the bacteria that cause body odour.
Catalysts: the high surface area to volume ratio means more of the catalyst's atoms are at the surface, so less catalyst is needed.
New uses of nanoparticles are an important area of research.
Advantages
diagram
Their very high surface area to volume ratio makes them very effective, so smaller quantities are needed.
Surface atoms are red. Smaller particles expose more atoms, so less catalyst is needed.
They can have useful properties that the bulk material does not have.
They are small enough to reach places that larger particles cannot, e.g. inside cells.
Possible risks
Nanoparticles are so small that they may be breathed in or absorbed through the skin, and could get into cells or the bloodstream.
Their different properties mean they might damage cells or be toxic, even if the bulk material is harmless.
They may be washed into the environment (e.g. from sun cream) and harm living things there.
Because nanoparticles are quite new, their long-term effects on health and the environment are not yet fully understood.
How to evaluate a use
Give the benefits, using the information in the question.
Give the risks or disadvantages.
Make a judgement with a reason, e.g. 'the benefits outweigh the risks because…, but more research into safety is needed'.
How to answer each type of question
Give uses of nanoparticles
1 to 2 marksGrade 4
Choose from the five areas: medicine, electronics, cosmetics and sun creams, deodorants, catalysts.
Give exactly the number asked for.
Example. Give two uses of nanoparticles.
Show the model answerHide the model answer
Any two from: medicine / drug delivery (1); electronics (1); cosmetics or sun creams (1); deodorants (1); catalysts (1). [max 2]
Don’t lose marks
Giving only advantages, or only risks, in an 'evaluate' question.
Writing a conclusion with no reason. Say why the benefits do or do not outweigh the risks.
Saying nanoparticles are definitely dangerous or poisonous. The risks are possible and not yet fully understood.
Ignoring the data in the question. Quote the figures you are given.
More tips
Memory tricks
Five uses, 'My Electric Sun Deodorant Catalyses': Medicine, Electronics, Sun creams (and cosmetics), Deodorants, Catalysts.
Evaluate = for, against, verdict. No verdict, no top marks.
Every advantage comes back to the high surface area to volume ratio; every risk comes back to 'small enough to get into the body, and long-term effects unknown'.
Exam technique
In 'evaluate' questions, use the information in the question: it is there to be used.
Explain each point: 'blocks more UV, so less risk of sunburn' scores more than 'it is better'.
Finish with a judgement that follows from the points you have made.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 4
List the main uses of nanoparticlesMedicine, electronics, cosmetics and sun creams, deodorants, and catalysts.
Grade 5
Give advantages of using nanoparticlesTheir high surface area to volume ratio makes them effective, so smaller quantities are needed.
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
Nanoparticles have many applications.
(a) Give two areas in which nanoparticles are used.[2]
(b) Silver nanoparticles are added to some wound dressings. Suggest why.[1]
(c) Give one possible risk of using nanoparticles.[1]
Show the answer and mark scheme
(a)Answer: e.g. medicine; sun creams
medicine
electronics
cosmetics
sun creams
deodorants
catalysts
(b)Answer: They kill bacteria.
they kill bacteria / are antibacterial / prevent infection
(c)Answer: They may be absorbed into the body and harm cells; their long-term effects are not known.
may be breathed in / absorbed into the body or cells and cause harm / long-term effects are unknown / may harm the environment
Question 2Medium5 marks
Some sun creams contain nanoparticles of titanium dioxide. The nanoparticles absorb or reflect harmful ultraviolet (UV) light. Older sun creams contained larger particles of titanium dioxide, which left a white layer on the skin.
(a) Suggest two advantages of using nanoparticles of titanium dioxide in sun cream.[2]
(b) Suggest two reasons why some people are concerned about using nanoparticles in sun cream.[2]
(c) Explain why a smaller mass of titanium dioxide is needed when it is used as nanoparticles.[1]
Show the answer and mark scheme
(a)Answer: Better skin coverage and more effective protection from UV; the cream does not leave a white layer.
better skin coverage
more effective protection from UV light / less needed
does not leave a white layer / is invisible on the skin
(b)Answer: The nanoparticles might pass through the skin into cells, their long-term effects are unknown, and they may harm the environment when washed off.
nanoparticles may pass through the skin / into the body or cells
long-term health effects are not yet known
nanoparticles washed off into the sea / water may harm organisms / the environment
(c)Answer: Nanoparticles have a much higher surface area to volume ratio.
nanoparticles have a (much) higher surface area to volume ratio