CHAPTER 10: RADIOACTIVITYThe process of Transmutation plus

10.4 Fission and Fusion

TRANSMUTATION

Transmutation is the process of converting atoms of one element into a different element.

When unstable radioisotopes give off alpha or beta particles the atom will change its proton number so they will become a different element completely.

ALPHA TRANSMUTATION

Transmutation involving an alpha particle will cause the atom to lose two protons and two neutrons. As this is the case, the atom will decrease by two in atomic number and by four in the mass number

Alpha transmutation of Uranium-238

BETA TRANSMUTATION

Transmutation involving an beta particle not cause the mass of the atom to change (as it is only losing an electron) but it will cause the atomic number of the element to increase by one since a neutron changed into a proton.

In this case, a Carbon-14 atom gives off a beta particle and is transmutated into a Nitrogen-14 atom.

SO WHAT CAUSES A NUCLEUS TO BE UNSTABLE?

We already know that opposite charges attract. This is due to what is called the electromagnetic force. It is also true that like charges repel.

So, how can a nucleus that is made up of protons(+) and neutrons (n.c.) stay together?

The nucleus of an atom is held together by a force called the strong nuclear force. The strong nuclear force is about 100 times greater than the electromagnetic force but is only good over very short distances.

UNSTABLE NUCLEI

If a nucleus has a lot of protons and neutrons, enough distance can be created between some protons to cause the electromagnetic force to be greater than the strong nuclear force.

In fact, this is always the case with any atom with an atomic number greater than 83 is radioactive (will decay and give off radiation).

NUCLEAR FISSION

Nuclear Fission is the process of splitting an atom into two smaller parts. When this occurs, huge amounts of energy are produced from very small amounts of mass.

FISSION

Nuclear Fission is what happens to produce energy in a nuclear power plant and what also happens in a nuclear bomb explosion.

The difference between the two is control of how much energy is released over time. A nuclear explosion occurs due to an event called a chain reaction occurring which releases too much energy too fast.

In a nuclear power plant, steps are taken to reduce the rate of nuclear fission to control energy flow rates.

NUCLEAR POWER – ADVANTAGES/DISADVANTAGES

Nuclear power plants produce energy without causing the air pollution like coal power plants.

Even though that is a great selling point for nuclear power, there are far more disadvantages in its use.

Nuclear waste produced in fission reactions is highly radioactive and will be for tens of thousands of years. This makes disposal very expensive and very hazardous for all life forms. One other thing to think about…Chernobyl.

FUSION

Fusion is the process of combining two atoms to form one larger atom. This happens on the Sun!

Fusion only occurs in the plasma state which is at very high temperatures. We can not achieve fusion on Earth as we can not generate high enough temperatures to start the reaction and we can’t contain the plasma if we could. Too bad as fusion produces much more energy than fission and has no hazardous waste.

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Fusion

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