Name______Period:______Date:______Fission/Fusion Worksheet _K

Nuclear Weapons

There are two main types of nuclear weapons: atomic bombs, which are powered by fission reactions similar to those in nuclear reactors [power plants], and hydrogen bombs, which derive their explosive power from fusion reactions.

An atomic bomb slams together two pieces of fissionable material, usually uranium-235 or plutonium-239, creating critical mass. This releases its energy instantaneously as atoms inside it split in an uncontrolled chain reaction. On August 6, 1945, an atomic bomb called Little Boy was dropped on the Japanese city of Hiroshima, followed three days later by another, called Fat Man, on Nagasaki.

Hydrogen bombs fuse together hydrogen atoms to form heavier helium atoms, releasing far more energy than a fission bomb. Two isotopes of hydrogen are used – deuterium (2 neutrons) and tritium (3 neutrons). Hydrogen bombs have never been used in war and are thousands of times more powerful than atomic bombs.

Directions: Identify each as a fusion , fission , or both kinds of reactions:

1. Used in nuclear power plants:

2. Occurs on the sun:

3. More power per gram:

4. A larger nucleus divides to make a smaller nucleus:

5. Two hydrogen atoms fuse to make a helium atom: ______

6. A critical mass is necessary to explode: ______

7. :

8. An atomic bomb: ______9. is the minimum amount of material needed to sustain a nuclear reaction.

10. are used in nuclear power plants to keep the reaction under control.

11. is a series of fission/fusion reactions.

12. Why can’t we use fusion reaction in a nuclear power plant? ______

13. What is the downside to fission reactions used in power plants? ______14. How is electricity generated from nuclear power plants? ______

15. Is cold fusion possible? _____

Complete the following fission and fusion nuclear equations. Indicate if the equation represents fission or fusion (circle one)

231Pa  192 Ir + ______1. 91 77

Fission or fusion

244Pu  141 Pr + ______2. 94 59

Fission or fusion

4He + 2 H  ______3. 2 1

Fission or fusion

9Be + 12 C  ______4. 4 6

Fission or fusion

238U  128 Te + ______5. 92 52

Fission or fusion

56Fe + 59 Ni  ______6. 26 28

Fission or fusion

7. 262Db  96 Mo + 28 Si + ______105 42 14 Fission or fusion

265Hs  16 O + 9Be + ______8. 108 8 4

Fission or fusion