Splitting a large nucleus into two smaller nuclei

Usually begins by bombarding (shooting at) nucleus with a neutron become unstable Nucleus split into 2 (roughly half the mass each, but not usually equal)

Tip to recognize FISSION Equations: Usually involved “big” isotopes breaking into 2

Nuclear fission reactions produce a lot of energy(Comes from converting mass to energyE=mc2) Can produce more than 2 nuclei

To figure out the missing part of the equation:do the mathfind the identity of element using atomic # Can produce/ require multiple neutrons, so make sure that you have accounted for the coefficient in front of 1n

0**Let’s look at Sample Problem on p. 314

Fission bomb= Atomic bomb

Keep two separate masses of Uranium or Plutonium.

The moment they combine (by implosion, or forcing two parts together), the radioactive material will reach “critical mass” and will react faster and faster until the material is used up EXPLOSION!!!

E.g. Bomb dropped in Hiroshima and Nagasaki

Basic principle start CHAIN REACTION of Fission Reactions

Usually use Uranium-235 Use a moderator to

control chain reactions (can use heavy water, cadmium or boron rods to absorb neutrons)

E.g. CANDU reactors (Canadian Deuterium, and Uranium)

Process occurs in the SUN (supply energy needed on Earth to sustain life!)

“Fusing” or joining of two small nuclei to make one large nucleus

Tip to recognize FUSION Equations:Usually involves “smaller” isotopes

(Helium, Hydrogen, Deuterium, Tritium etc.)

Hydrogen 1p, 1 e; 0 n

Deuterium Hydrogen atom

with 1 p, 1 e and 1 n

Tritium Hydrogen atom

with 1 p, 1 e and 2 n

Simplest fusion equation

How to make Helium atoms:

0 e (positron)+1

FUSION REACTIONS Hydrogens undergo fusion to become He 2 Helium nuclei fuse to make Beryllium Beryllium and Helium fuse to make Carbon!

Fusion bomb= Thermonuclear bomb=Hydrogen bomb

Use energy from a fission bomb to power fusion bomb (bomb within a bomb)