Why Is Krypton the Product in This Nuclear Reaction?

Click For Summary
SUMMARY

The nuclear reaction involving Uranium-235 and a neutron produces Barium-141, Krypton-92, and three additional neutrons along with 202.5 MeV of energy. The element X in the reaction is identified as Krypton, which has an atomic number of 36. The solution requires understanding the conservation of atomic numbers and mass numbers, leading to the conclusion that the missing element must balance the equation. The approach to solving this problem involves recognizing the significance of atomic numbers in identifying elements.

PREREQUISITES
  • Understanding of nuclear reactions and fission processes.
  • Knowledge of atomic numbers and mass numbers in chemistry.
  • Familiarity with energy units, specifically MeV and their conversion to joules.
  • Basic grasp of the mass-energy equivalence principle (E=mc²).
NEXT STEPS
  • Study the principles of nuclear fission and the role of neutrons in reactions.
  • Learn about the periodic table and how to determine atomic numbers and mass numbers.
  • Explore energy conversion from MeV to joules and its applications in nuclear physics.
  • Review the mass-energy equivalence formula and its implications in nuclear reactions.
USEFUL FOR

Students preparing for physics exams, educators teaching nuclear physics concepts, and anyone interested in understanding nuclear reactions and element identification.

Hooly
Messages
3
Reaction score
0
Can someone please explain to me why the answer to the following question is Krypton? A step by step solution would be ideal please!

(b)The following reaction occurs in a nuclear reactor:

235U+01n →141Ba+X+301n+202.5MeV
(i) Identify the element X.

Many thanks!
(Question is Q12 b part i from the 2010 Irish state physics exam http://examinations.ie/archive/exampapers/2010/LC021ALP000EV.pdf )
 
Last edited by a moderator:
Physics news on Phys.org
I initially took this approach;
235 + 1 -141 -3(1) which is equal to 92. When I checked the answer this was incorrect. Then went down the route of converting the MeV to joules and subbing that value into the mass- energy equivalence formula in order to find the mass, and then using the unified atomic mass unit value (1.6605402x10^-27 kg) to try to find the element represented by the energy, at which point I got lost and have been unable to proceed further. Bear in mind I am 18 and studying for my Leaving Cert in Ireland (equivalent of SATs in US I think) so I am not at an advanced level
 
Which number determines the chemical element?
 
Do you guys just reply with questions? :P But yes I realized earlier that atomic number was the way to go, wasn't thinking straight, over complicated it. Many thanks ✌️
 
Hooly said:
Do you guys just reply with questions? :P
The idea is to help you to find the answer, and questions often work best.
 

Similar threads

Are These Statements About Nuclear Physics True or False?
  • · Replies 2 ·
Replies
2
Views
2K