This set of Applied Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “Carbon Nano Tubes”.
1. Carbon nano tubes are the sheets of graphite about ________
Explanation: Carbon nano tubes are the sheets of graphite about 0.4nm in diameter. They are rolled up to make nm in diameter. They are very small in size.
2. Carbon nano tubes are also called as ________
a) Bucky tubes
b) Bulky tubes
c) Bulk tubes
d) Buck balls
Explanation: Carbon nano tubes are also called as bucky tubes because they are also made up of graphite and they are in the form of tubes instead of balls. So, they are also called as bucky tubes.
3. Carbon nano tubes are first observed in _________
Explanation: Carbon nano tubes are observed in an year 1991 in the soot of the graphite during the arc discharge. First production of CNT was in 1992 by arc discharge method.
4. In how many methods the CNT can be prepared?
Explanation: The carbon nano tubes can be prepared in 4 types. They are: 1. arc discharge method, 2. laser ablation method, 3. plasma torch method, 4. chemical vapour deposition method.
5. The current used in the arc discharge method is about _________
Explanation: The current used in the arc discharge method is about 100mA. By arc discharge of graphite electrodes in presence of ionised gas to reach high temperatures.
6. The carbon contained in the negative electrode sublimates.
Explanation: The carbon contained in the negative electrode sublimates because of high discharge temperature. This method is widely used method.
7. The yield of the laser ablation is ______________
Explanation: The yield of the laser ablation is 70%. The reaction temperature determines the diameter of the single walled CNT.
8. Laser ablation method is developed by _______
b) Richard Smalley
c) Watson and crick
d) Neils bohr
Explanation: Laser ablation method is developed by Dr. Richard Smalley at rice university, USA. In this process a pulsed laser vaporises a graphite target.
9. A water cooled surface is used in the process to collect __________
a) Nano particles
b) Nano tubes
c) Nano spheres
d) Nano sheets
Explanation: A water cooled surface is used in the process to collect the nano tubes. While an inert gas is blend into chamber, the nano tubes settles on cooler surfaces.
10. To improve the composite of graphite _______ is used as catalyst.
c) CO and NI
Explanation: To improve the composite of graphite CO and NI mixture is used as catalyst. They are used to synthesise the single walled CNT.
11. Plasma torch method is used in the year ________
Explanation: Plasma torch method is used in the year 2005 at national research council of Canada. It is used to make the single walled CNT.
12. Plasma torch method is similar to the __________
a) Laser ablation
b) Arc discharge
c) Chemical vapour decomposition
Explanation: plasma torch method is similar to the arc discharge method. It is first started to make the single walled CNT in 2005.
13. Plasma torch method is produces ______ of CNT per minute.
Explanation: Plasma torch method is produce 2gms of CNT per minute. A metal crystal is used. In a thermal plasma torch method is a high frequency oscillating current in a coil.
14. Chemical vapour decomposition is developed in an year ________
Explanation: Chemical vapour decomposition is developed in a year 2007 at university of Cincinnati, USA. In this method the substrate is prepared with a layer of metal catalyst nano particles.
15. The substrate is heated to ________
Explanation: The substrate is heated to 700C and a mixture of nitrogen and carbon containing acetylene or ethylene or ethanol or methane was passed.
Sanfoundry Global Education & Learning Series – Applied Chemistry.
To practice all areas of Applied Chemistry, here is complete set of 1000+ Multiple Choice Questions and Answers.