Question 19M.3.hl.TZ1.6
| Date | May 2019 | Marks available | [Maximum mark: 3] | Reference code | 19M.3.hl.TZ1.6 |
| Level | hl | Paper | 3 | Time zone | TZ1 |
| Command term | Describe, Suggest | Question number | 6 | Adapted from | N/A |
Nanotechnology has allowed the manipulation of materials on the atomic level.
Describe the structure and bonding of a carbon nanotube.
Structure:
Bonding:
[2]
Structure:
giant covalent/network covalent [✔]
Bonding:
each carbon covalently bonded to 3 other carbons
OR
each bond has order of 1.5 [✔]
Note: Accept “cylindrical/tube shaped”.
Accept “has delocalized electrons” OR “has sp2 hybridization”.
Describing the structure and bonding of a carbon nanotube was generally answered satisfactorily, although some candidates simply said the bonding was covalent with no further detail.
Suggest one application for carbon nanotubes.
[1]
Any one of:
3D electrodes [✔]
catalysts [✔]
biosensors [✔]
molecular stents [✔]
body armour [✔]
synthetic muscles [✔]
micro transistors/circuitry/capacitors/electrodes [✔]
reinforcing phase in a matrix/composite material «such as concrete» [✔]
micro antenna [✔]
stealth technology [✔]
water/air filtration [✔]
solar cells [✔]
tennis racquets [✔]
microelectronic circuits [✔]
Note: Do not accept just general answers such as “medicine” or “defence”.
There were some vague responses for applications of carbon nanotubes when specific details were needed to score the mark in (b).