GCSE Chemistry Carbon & nanoparticles questions by topic

Complete the sentences about the structure of two allotropes of carbon.

1. (a)In diamond, each carbon atom forms … covalent bonds.[1]
2. (b)In graphite, each carbon atom forms … covalent bonds.[1]
3. (c)Name the particles that move through graphite when it conducts.[1]
4. (d)Name the weak forces between graphite’s layers.[1]

Match each use to the material that suits it best.

1. (a)Name the material for the cutting tool tip.[1]
2. (b)Name the material for the electrode in electrolysis.[1]
3. (c)Name the material for reinforcing the racket frame.[1]

Nanoparticles are used in sunscreens and in catalysts.

1. (a)State the size range of nanoparticles in nanometres.[1]
2. (b)Explain why nanoparticle catalysts work well from very small masses.[2]
3. (c)State one possible risk of using nanoparticles in cosmetics.[1]

A scientist compares two carbon samples: one from a pencil “lead”, one from a jewellery diamond.

1. (a)Name the allotrope in each sample.[1]
2. (b)State two property differences between the allotropes.[2]
3. (c)State one property the two samples share.[1]

A class builds ball-and-stick models of diamond and graphite.

1. (a)State how many sticks should meet at each ball in the diamond model.[1]
2. (b)State how many sticks should meet at each ball in the graphite model.[1]
3. (c)The teacher hands out spare “electron” tokens. State which model should receive them and how many per carbon atom.[2]
4. (d)Name the weak forces that the graphite model should suggest between its layers.[1]

Explain the following observations about graphite.

1. (a)Graphite conducts electricity but diamond does not.[3]
2. (b)Graphite is used as a dry lubricant in locks.[2]
3. (c)Graphite has an extremely high melting point despite its softness.[1]

Fullerenes were discovered in the 1980s and now appear in consumer products.

1. (a)Describe the structure of buckminsterfullerene, C₆₀.[2]
2. (b)Explain why fullerenes can deliver medicines to specific sites in the body.[2]
3. (c)State one further use of spherical fullerenes.[1]

A nanoparticle catalyst speeds up the decomposition of hydrogen peroxide. A student suggests using an equal mass of the same substance as a coarse powder instead.

1. (a)Explain why the nanoparticle version gives the faster reaction.[3]
2. (b)A 1 cm cube of catalyst has SA 6 cm². It is cut into 8 cubes of side 0.5 cm. Calculate the new total surface area and the new SA:V ratio.[3]

A sunscreen uses nano-sized titanium dioxide instead of the older coarse powder.

1. (a)Explain one advantage of the nano-sized particles for the user.[2]
2. (b)Explain one concern a scientist might raise about nano-sunscreens.[2]
3. (c)Suggest what should be done before the product is approved for wide sale.[2]

C₆₀ is a simple molecular substance; graphite is not.

1. (a)Describe the structure and bonding within one molecule of C₆₀.[2]
2. (b)C₆₀ turns to vapour far below graphite’s melting temperature. Explain why.[2]
3. (c)State whether solid C₆₀ conducts electricity, and explain your answer.[2]

A 1 mm cube of silver is divided into identical cubes of side 0.1 mm.

1. (a)How many small cubes fit along one edge of the original cube?[1]
2. (b)Calculate the total number of small cubes.[1]
3. (c)Each small cube has surface area 0.06 mm². Calculate the new total surface area, and state how many times larger it is than the original cube’s surface area.[3]
4. (d)Name one application that exploits this increase.[1]

This question compares diamond and graphite in an industrial setting.

1. (a)An electrolysis cell uses graphite electrodes carrying current into molten sodium chloride. Explain why graphite works and diamond would not.[4]
2. (b)The electrodes slowly wear away as the cell runs. Suggest, in terms of structure, why graphite can be worn away while diamond cannot be scratched.[2]

A pharmaceutical company evaluates two delivery methods for a cancer drug: attaching it to C₆₀ fullerenes, or grinding the drug into nanoparticles of its own.

1. (a)Describe the trend in the data and explain it using particle size.[3]
2. (b)Explain why smaller particles show the pattern you have described, referring to surface area and passage into cells.[2]
3. (c)State one additional safety question the company should answer before choosing the fullerene method.[2]

A student claims: “Nanoparticles are just very small bits of the same material, so any product using them is as safe as the bulk version.”

1. (a)Give two reasons why the student’s reasoning is incomplete.[4]
2. (b)The student’s second claim is that the useful properties of nanoparticles come from their chemical composition. Correct the claim.[2]

An electronics firm must connect a microchip to a sensor with a conducting track only nanometres wide.

1. (a)Suggest whether diamond or graphene suits the track, explaining the electronic structures fully.[4]
2. (b)The track must also survive repeated bending when the device flexes. State which property of graphene helps, and why diamond would fail.[2]

A factory makes composite materials containing carbon nanotubes. Safety officers note that long, straight nanotubes resemble asbestos fibres in shape and size.

1. (a)Explain why nanotubes could be harmful if workers breathe them in.[2]
2. (b)Explain why manufacturers use nanotubes in composites anyway.[2]
3. (c)State two precautions the factory should take to protect its workers.[2]

Explain, in terms of structure and bonding, why diamond is chosen for saw blades and drill tips while graphite is chosen for pencil “leads” and lubricants, even though both are pure carbon.

1. (a)Describe the bonding arrangement in each allotrope.[2]
2. (b)Explain why diamond suits cutting tools.[2]
3. (c)Explain why graphite suits pencils and lubricants.[2]

A textbook shows C₆₀ three ways: a flat 2D diagram, a ball-and-stick model, and a computer 3D model.

1. (a)State one limitation of the flat 2D diagram for showing C₆₀.[2]
2. (b)State what the ball-and-stick model shows well and one thing it exaggerates or omits.[2]
3. (c)State which representation is best for showing the cage shape, and why.[2]