Nuclear Fusion Reactions

Essential Standard 2.3

Understand the role of the nucleus in

radiation and radioactivity.

Learning Objective 2.2.6

Compare nuclear reactions including

alpha decay, beta decay, and gamma

decay; nuclear fusion and nuclear fission.

I Can StatementsAt the end of this lesson, you should be

able to say, with confidence:

• I can distinguish between a chemical

reaction and a nuclear reaction.

• I can distinguish between nuclear fusion

and nuclear fission reactions.

• I can explain where, how, and what is

produced during fusion reactions.

Chemical ReactionsDuring chemical reactions, atoms are not created nor

destroyed, only rearranged.

That’s why chemical

equations had to be

balanced with the

same number of atoms

on the reactant side as

the product side.

Also, only valence electrons are involved in

chemical reactions.

Nuclear ReactionsDuring nuclear reactions, atoms are created and

destroyed or at least, turned into other types of atoms.

Nuclear reactions also

take place inside the

nucleus of the atom,

which is why they’re

called nuclear

reactions.

Nuclear ReactionsThere are two types of nuclear reactions:

Nuclear Fusion and Nuclear Fission.

Nuclear Reactions

During nuclear fusion

reactions, smaller particles or

atoms are fused together to

form larger atoms.

During nuclear fission

reactions, larger atoms

split apart into smaller

atoms and particles.

Nuclear FusionNuclear fusion reactions take place inside of stars,

like our Sun.

Fusion can be distinguished from fission, because

the word fusion has the letters for Sun within the

word fusion.

PlasmaInside stars, like our Sun, the temperatures are so

high that most matter actually exists as plasma,

not as atoms.

Plasma is not made up of atoms, but is made up of

lone protons, neutrons, and electrons.

The high temperatures,

inside the core of the Sun,

transfer thermal energy to

the particles, setting them in

motion at extreme speeds.

As the particles move,

they collide and fuse

together, forming

atoms, in a process

called fusion.

Fusion

As small particles or atoms fuse together, a large

amount of energy is released.

Energy

Albert Einstein’s famous equation, E = MC2,

is derived from nuclear fusion reactions.

E – energy M – mass C – speed of light

The energy released during fusion reactions,

travels outwards, from the stars, in the form of

electromagnetic waves.

Electromagnetic Waves

Visible Fusion ReactionsHuman eyes are able to see the energy, released by stars during fusion reactions, as light waves.

Formation of AtomsFor most of a star’s life,

Hydrogen isotopes are fused

together to form Helium atoms.

Later, lithium

atoms begin to be

formed and then

beryllium atoms.

Formation of AtomsHelium and beryllium atoms then fuse to form carbon

and oxygen atoms.

Fusion inside of stars and the formation of larger

and larger atoms continues up through the

formation of iron atoms.

SupernovaAfter stars get to the iron formation stage, it explodes

during a large supernova event, and all the atoms

formed inside the star are shot out into space.

As the atoms are shot out

into space, the collide to

form even larger atoms.

92 types of atoms are

formed through this

fusion process.

Star DustOvertime, gravity pulls the atoms together to form

nebulas, galaxies, and solar systems.

Our world and everything on it, including you, are

formed from atoms that were fused together inside

of stars that are long gone.

In a way, you can think of yourself as being made

up of star dust.

Currently there are 118 known elements, 92 of which are

formed through natural fusion reactions.

Naturally Formed Elements

Particle AcceleratorsThe other elements are formed by man inside giant

particle accelerators.

Inside long tubes,

atoms are shot at each

other so the can collide

to form atoms.

Because the particle accelerator tubes have to be so

long, they are located in underground labs.

Particle AcceleratorsThe circles in the photo, below, represent where the

particle accelerator tubes are located underground at

CERNS, near Geneva, Switzerland.

The End