Questions:
1. This material is one of the lightest solids known, since more than 99% of its composition by volume is air. Making it involves extracting the liquid component of a particular type of semisolid by supercritical freezing. Name it.
2. In the 1970s, a British hairdresser named Maurice Ward developed a material his granddaughter called ________. He claimed, and which some independent tests upheld, that it could withstand extreme heat, although attempts to use it to line induction furnaces failed. Fill in the blank.
3. This material is the world’s second most used after water. While it is very strong, it has low tensile strength and is thus prone to cracking. Over the centuries, scholars have tried to develop “self-healing” versions of this material, including, most recently, bacteria-based efforts. Name the material.
4. In the 1986 Star Trek film ‘The Voyage Home’, two characters trade a formula for transparent aluminium in return for other items. Name the ceramic compound of the metal that is actually transparent, and has also been shown to withstand armour-piercing bullets.
5 Like graphene, a one-atom layer of bonded carbon atoms, stanene is a layer of ___ atoms. This sheet is of interest to materials scientists because it’s expected to be a topological insulator, i.e. able to conduct electricity only along its surface. Fill in the blanks.
Visual:
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This element joins Cs, Rb, and Hg as a non-radioactive metal near room-temperature as well as Si, Ge, Bi, and Pu as elements whose liquid forms are denser than their solid forms. Name it.
Answers:
1. Aerogel
2. Starlite
3. Concrete
4. Aluminium oxynitride
5. Tin
Visual: Gallium
Published – February 21, 2025 11:00 am IST