CH 2952 – NUCLEAR AND RADIOCHEMISTRY

Date & Time : 26-04-2006/9.00-12.00 Dept. No. Max. : 100 Marks

Part A

Answer the following 10´2 = 20

What are isotones? Give an example.
What is nuclear quadrupole moment?
Mention the nuclear spin of (a) ¹²C (b) ²H .
What is internal conversion?
Give the mechanism of positron emission.
How is the odd – even rule useful in predicting stability of a nucleus?
Show that t_1/2= 693/λ
How are thermal neutrons obtained?
What is the final product obtained if 2 α and 4 β^–particles are emitted from ²³⁶U?
Explain tunneling effect.

Part B

Answer any eight of the following: 8´5 = 40

Write a note on nuclear forces.
Discuss the stability of the nucleus based on n/p ratio.
Discuss the principle of Dempster mass spectrograph.
Write a note on proportional counters.
What is double β decay?
What mass of ¹⁴C with t_1/2 = 5730y has an activity equal to one curie?
How is radius of a nucleus deduced? Calculate density of ⁸¹
What is electron capture? What are its consequences?
Why are the atomic weights of elements found in fraction?
What is the significance of interaction of radiation with water?
What is the principle of isotope dilution analysis? What are the disadvantages of this technique?
Write a note on use of radio isotopes in determination of mechanism of a reaction.

Part C

Answer any four of the following: 4´10 = 40

How is binding energy calculated theoretically using liquid drop model?
Describe the mechanism of β decay emission. Explain the forbidden and allowed transitions of β decay using Kurie plot.
Write a note on (a) Geiger Counter (b) Scintillation counter
Discuss the use of nuclear shell model in explaining magic numbers.
How is the factor binding energy per nucleon significant in deciding stability of a nucleus?
Discuss working of a nuclear reactor.