74.nuclear fission
TRANSCRIPT
Author : Khairi
NUCLEAR FISSION
A process of splitting of a heavy nucleus into two lighter nuclei
The heavy nucleus is bombarded by a neutron
At end of the process,it produces ;
Two new nuclei Three neutrons Nuclear energy
Author : Khairi
NUCLEAR FISSION EQUATION
U23592 Kr92
36Ba14156n1
0+ + + n1
03 + energy
EXERCISE
Calculate the nuclear energy produced in the nuclear fissionabove in Joule and eV.
2.69 x 10-11 J
Uranium-235 = 235.04 a.m.uKrypton-92 = 91.93 a.m.uBarium-141 = 140.91 a.m.uNeutron = 1.01 a.m.u
NUCLEAR FISSION
Author : Khairi
Mass defect = mass before – mass after
= [235.04 + 1.01] – [140.91 + 91.93 + 3(1.01)]
= 0.18 a.m.u
= 0.18 x 1.66 x 10-27 kg
= 2.988 x 10-28 kgE = mc2
= 2.988 x 10-28 x (3.0 x 108)2
= 2.69 x 10-11 J
NUCLEAR FISSION
= 1.68 x 108 eV
U23592 Kr92
36Ba14156n1
0+ + + n1
03 + energy
NUCLEAR FISSION EQUATION
Author : Khairi
CHAIN REACTION
A chain reaction occurs when a further nuclear fission is continuously occurred.
This is happen when the neutron which is produced in earliernuclear fission bombarding the new nuclei.
Again,the process will produce 2 new nuclei,3 neutron and nuclearenergy.
Chain reaction only can happen when the mass of uranium isexceeded the critical mass.
NUCLEAR FISSION
Author : Khairi
In the fission reaction for an atom of uranium-235,the energyproduced is 2.9 x 10-11 J.What is the total loss of mass in the reaction ?
A. 3.22 x 10-28 kg
B. 9.67 x 10-20 kg
C. 2.61 x 106 kg
D. 1.03 x 1019 kg
E = mc2
2.9 x 10-11 = m x (3 x 108)2
m = 3.22 x 10-28 kg
PAST YEARS QUESTIONPAST YEARS QUESTION
Author : Khairi
a. What is meant by nuclear fission ?
A process of splitting a heavy nucleus into two lighter nuclei
b. What is meant by nuclear fusion ?
A process of combining two heavy nuclei to form a heavier nucleus
PAST YEARS QUESTIONPAST YEARS QUESTION
Author : Khairi
c. Using the information in the table,compare the nuclear fission and nuclear fusion.Hence state the relationship between mass and energy evolved.
1. Nuclear fission is a process of splitting a heavy nucleus to lighter nuclei while nuclear fusion is a process of combining light nuclei to heavier nucleus
2. Both reactions release nuclear energy
3. Nuclear energy released due to mass loss
PAST YEARS QUESTIONPAST YEARS QUESTION
Author : Khairi
Describe how the chain reaction happens in a nuclear fission of an atom of uranium.
neutron
Heavy nucleus
3 neutrons
Light nucleus
Heavy nucleus
Heavy nucleus is bombarded by neutron
Two lighter nuclei and three neutron are produced
Neutron continue to hit the new nuclei and produce twolighter nuclei and three neutron
PAST YEARS QUESTIONPAST YEARS QUESTION