Nuclear Energy

Strong Nuclear Force

As one of the 4 fundamental forces of nature, this is the one that is used to keep nucleons together. Without the strong nuclear force nucleons would never stay together but rather go off in all sorts of different directions.

Binding Energy

This is the amount of energy that is needed to be put into the nucleus to be able to tear it apart. Not to be confused with the Strong Nuclear Force, which is used to keep the nucleus together.

Transmutation

The process of turning one element into another. It's always referred to as the alchemist's dream, to be able to turn dirt into gold. In reality, this example is not completely accurate but can give a good idea of the process.

E=mc²

Originated by our favorite physicist, Albert Einstein. This equation shows us that energy is directly proportional to the amount of mass that an object holds, and vice versa. Will help us understand radiation and decay.

What is Nuclear Energy?

Although it's a very intimidating word and phrase, Nuclear Energy simply refers to the energy that is used inside of an atom's nucleus. This sets it apart from most other chemical interactions, as most simply deal with an atom's valance electrons and not interactions within the nucleus of an atom.

So, what keeps a nucleus together?

a chart illustrating the binding energy
per nucleon

The chart above is used to illustrate the amount of energy needed to separate a nucleus.

Due to the Strong Nuclear Force's lessened abilities over larger nuclei, it becomes much easier to tear that nucleus apart the bigger it becomes. This is what ultimately sets the atom's stability.

Why does this matter?

a chart illustrating the number of neutrons for
each proton

Well once we know what keeps the nucleus together, we can much easier understand how to take them apart.

The chart above illustrates the relationship between the number of protons to neutrons. As we can see, the larger the amount of protons, the larger the number of neutrons that are needed to cancel out the proton's repulsion force.

This means that the larger the nucleus, the more unstable it is, and the easier it is for the element to decay.

What is an atom's decay?

Here we can see the amount of penetrating power each
type of decay has. Alpha is the weakest, then beta, and gamma the strongest.

Since we know that larger nuclei are easier to take apart, we must have a way to describe that process.

An Atoms decay is exactly that, the way the atom has to get rid of this excess energy and nucleons. It comes in three types, Alpha, Beta, And Gamma (with their respective strengths shown above).

The energy once you combine the entire nucleus vs each part.

How exactly do we calculate binding energy?

First of all, U is simply a unit to calculate the mass in microscopic ranges, called Unified Atomic Mass Unit, which is equal to 1.6605 x 10^-27 Kg. The blue unit in the picture (top), is the mass of the entire nucleus of a Helium atom. While the green unit (bottom) is the mass of each individual nucleon added together. Why is there more mass when added individually than as a whole? Well since we know that E=mc², we can rationally assume that the excess energy is simply binding energy.

Alpha Decay

This type of decay occurs because the parent nucleus is too large and the Strong Nuclear Force is no longer strong enough to hold all of the nucleons together.

Due to this instability, the nucleus must try to make itself smaller. It tries this by shedding two neutrons and two protons, what we call an alpha particle. This alpha particle is actually just a helium atom and is the same particle that Rutherford shot at a gold foil and discovered the Atoms nucleus.

We can also see that this process goes through Transmutation, where we go from one element to a completely different one.

Beta Decay

This type of decay usually happens when a nucleus has too many protons or neutrons. Here the atom will shed either a negative or positively charged beta particle (an electron) and a negatively or positively charged neutrino (a neutrally charged particle). Although an electron and antineutrino combo is far more common.

Originally the neutrino hadn't been included in the Beta Decay process. It wasn't until energy levels were measured in the decay and large fluctuations were found, leading to the idea that another particle must be carrying away this extra energy, the neutrino.

This type of Decay also goes through Transmutation.

A gamma-ray being emitted after the parent nucleus
couldn't handle that excess energy.

Gamma Decay

Gamma Decay happens when a nucleus emits high-powered photons, in what is known as gamma rays. This is different from other types of decay as it's actually a (very energetic) wave and not a particle.

This usually happens when the nucleus is decaying from a larger form and is in an excited state, or because it just collided with a very high-energy particle among other reasons.

Gamma Decay is also different from other types of decay as no transmutation occurs. This type of Decay is most seen in movies due to their very high penetrating power.

And what is radiation?

Using the same method as before to calculate binding energy, when we add together the masses of the parent nucleus and that of the products alone, we have a mismatch and seem to be missing some mass. What seems to be this missing mass? Well, that's radiation. It's to say, radiation is simply the kinetic energy of an element's decay. This kinetic energy is the same one that nuclear reactors harvest to be able to power entire cities. Incredible!