The Chemistry of the Fission Bomb


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This is the chemistry behind the fission bomb. Fission is the process in which an atom is forced into two lighter atoms with a neutron. I have always had a fascination with nuclear weapons. The amount of power behind the fission process is astronomical. For instance one pound of uranium has the firepower equivalent to 14 tons of coal! That’s an amazing amount of power for such a small package. Today we are going to find out what makes the fission bomb so explosive!

Composition of ...

  • Uranium235 or Plutonium239 (235U 239Pu)

  • Uranium/Plutonium core

  • Powerful explosives

  • mirror like coating (Beryllium oxide)

  • Deuterium or tritium (enhance uranium

Main Chemicals, Compounds, Components

The two main components are uranium and deuterium.

Uranium is the most essential part of the fusion bomb. It is a heavy metal with the symbol U and the atomic number 92. Uranium is a naturally occurring rare metal that has 3 isotopic forms, all of which are radioactive. 235U is what is used in the actual bomb and makes up only about .72% of all naturally occurring uranium. It is one of the few natural elements that is susceptible to fission. Deuterium is used to enhance the 235U and make it more fissable. Deuterium or with its symbol D is a heavy hydrogen that can be found most abundantly in the ocean. However it still only makes up .0156% of the oceans hydrogen.

Chemistry's Role

Uranium is most commonly obtained in open pit mines. A majority of the natural uranium is 238U which is virtually useless for making a fission bomb. 235U however is detrimental to creating a successful fission bomb. Since 235U makes up such a small portion of natural it needs to be separated from the rest of the uranium in a process called gaseous diffusion. In this process the uranium is turned into a gas and then sent through a series of porous walls. Since the 235U is lighter than 238U it travels more quickly and is therefore separated from the heavier uranium. Once fully extracted the remaining 235U is made into pellets ready to for the process of building the bomb.

Deuterium is extracted through seawater. It is a simple process where the deuterium (also known as heavy water) is separated from regular water with chemicals. The heavy water is charged, making the deuterium a gas which is now extractable.

Background Research

The fission bomb, more commonly known as the atomic bomb, is a nuclear weapon of mass destruction. With a process called fission an atom is split into two smaller atoms. Those atoms in turn will release neutrons of their own creating a chain reaction. The uranium core within the bomb is covered with a mirror like coating that will reflect neutrons back into the sphere and therefore amplify the detonation.


Nuclear fission

Gamma radiation

3 types of radiation

alpha, beta, gamma

radioactive isotopes decay into stable elements

Uranium isotopic forms

fission bombs are made of uranium235 or plutonium239

Uranium235 is naturally occurring

1 in 36 parts of all uranium

How to extract Uranium235

About the Author
Kallie is a junior at senior high school. She loves chemistry and learning how the world works. Kallie is a painter and is part of her school's honor band. She hopes to become a chemical engineer.