✅ Answer: B) Hexagonal (honeycomb) latticeGraphene is a single layer of carbon atoms arranged in a hexagonal (honeycomb) lattice. It is the thinnest material known (one atom thick). It is 200 times stronger than steel, conducts electricity better than copper, and is nearly transparent. Andre Geim and Konstantin Novoselov won the Nobel Prize in Physics 2010 for isolating graphene using Scotch tape. Graphene is the building block of graphite (pencil lead) and carbon nanotubes.

✅ Answer: B) GrapheneThe Nobel Prize in Physics 2010 was awarded to Andre Geim and Konstantin Novoselov for their groundbreaking experiments with graphene. They isolated graphene in 2004 using Scotch tape to peel layers from graphite. Graphene has extraordinary properties: strongest material, best conductor, thinnest material. The Nobel Prize for Fullerenes (C₆₀) was awarded in Chemistry 1996 (Curl, Kroto, Smalley). Quantum dots won the Nobel Prize in Chemistry 2023.

✅ Answer: B) 1–100 nanometresNanotechnology operates at the scale of 1–100 nanometres (nm). 1 nanometre = 10⁻⁹ metres = 1 billionth of a metre. For comparison: a human hair is ~80,000 nm wide; a DNA molecule is ~2 nm wide; a red blood cell is ~7,000 nm. At the nanoscale, materials exhibit unique properties different from their bulk form due to quantum effects and increased surface area. Richard Feynman’s 1959 lecture “There’s Plenty of Room at the Bottom” is considered the birth of nanotechnology.

✅ Answer: A) Emit different colours of light depending on their sizeQuantum dots are semiconductor nanocrystals (2-10 nm) that emit different colours of light depending on their size — smaller dots emit blue light, larger dots emit red light. This size-dependent optical property is due to quantum confinement effects. Applications: QLED TV displays (Samsung), solar cells, medical imaging, biosensors. Moungi Bawendi, Louis Brus, and Alexei Ekimov won the Nobel Prize in Chemistry 2023 for discovering quantum dots.

✅ Answer: C) 2007India’s Nano Mission was launched in 2007 by the Department of Science and Technology (DST) with an initial budget of ₹1,000 crore. It aims to promote basic research, develop infrastructure, build human resources, and foster international collaboration in nanotechnology. Key research centres: IIT Bombay, IIT Delhi, IISc Bengaluru, CSIR labs. India ranks among the top 5 countries in nanotechnology research publications globally.

✅ Answer: C) BuckyballsFullerenes (C₆₀) are also known as “Buckyballs” — named after architect Buckminster Fuller whose geodesic dome designs they resemble. They consist of 60 carbon atoms arranged in a spherical cage (like a soccer ball). They were discovered in 1985 by Robert Curl, Harold Kroto, and Richard Smalley (Nobel Prize in Chemistry 1996). Applications: drug delivery (can trap molecules inside), lubricants, superconductors, and solar cells.

✅ Answer: A) Delivers drugs directly to diseased cells, reducing side effectsNanomedicine’s targeted drug delivery uses nanoparticles to carry drugs directly to diseased cells (like cancer cells), reducing side effects on healthy cells. Traditional chemotherapy affects all rapidly dividing cells (including healthy ones), causing severe side effects. Nanoparticles can be engineered to recognise and bind to cancer cells specifically. Liposomal doxorubicin (Doxil) is an approved nano-drug for cancer. mRNA vaccines (Pfizer, Moderna) use lipid nanoparticles to deliver mRNA.

✅ Answer: A) Among the strongest materials known, yet extremely lightweightCarbon nanotubes (CNTs) are among the strongest materials known — about 100 times stronger than steel — yet extremely lightweight. They also have excellent electrical and thermal conductivity. CNTs are essentially rolled-up sheets of graphene. Applications: composite materials (aerospace, sports equipment), electronics (transistors), drug delivery, sensors, and energy storage. Single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) are the two main types.

✅ Answer: A) Richard FeynmanRichard Feynman is considered the “Father of Nanotechnology” for his 1959 lecture “There’s Plenty of Room at the Bottom” where he first envisioned manipulating matter at the atomic scale. Norio Taniguchi coined the term “nanotechnology” in 1974. Eric Drexler popularised nanotechnology with his 1986 book “Engines of Creation.” Andre Geim discovered graphene (Nobel Prize 2010). Richard Feynman also won the Nobel Prize in Physics 1965 for quantum electrodynamics.

✅ Answer: A) Bacteria, viruses, heavy metals, and chemical pollutantsNano water filters can remove bacteria, viruses, heavy metals (arsenic, lead), and chemical pollutants from water. They use nanomaterials like carbon nanotubes, graphene oxide, and nano-silver. Nano-silver has antimicrobial properties. These filters are more effective than conventional filters and can work without electricity. They are particularly useful for rural areas in India where clean water access is limited. India’s CSIR labs are developing affordable nano water purification systems.