Nuclear Chemistry and Radioactive Decay

By Christa RossOECS 110 A70Final Project

Brief IntroductionIn nuclear chemistry, radioactive decay is the spontaneous disintegration of a radionuclide accompanied by the emission of ionizing radiation by alpha or beta particles or gamma rays.

It is the changing of an unstable element (natural or isomer) to a stable element (natural or isomer).

Notation

Nuclear notations are used to represent the decay of one element into another. The formula for a radioactive element is:

XMass Number

Atomic Number

The atomic number and the atomic symbol (shown here as X) can be found in the periodic table.

Alpha DecayAlpha decay (α) occurs when the nucleus has too many protons, causing excessive repulsion. A Helium nucleus is emitted, stabilizing the nucleus.

He263

106Sg →

259

104Rf +

4

2This can also be written as: 4

2 αThis is the new atomic number and can be found in the periodic table.

Beta DecayBeta decay is when neutron/proton ratio is imbalanced in the nucleus, causing instability. There are two major types:• When the neutron/proton ratio is too great, an electron is

emitted, this is known as beta particle/electron ():

+

• When the neutron/proton ratio is too small, a proton turns to a neutron, this is known as positron ():

+

Also written

Gamma Decay

Gamma decay occurs when a nucleus is at too high of an energy level. The nucleus releases energy by emitting a high-energy photon known as a gamma particle (ϒ):

+ +

Conclusion

Radioactive decay is an important topic in nuclear chemistry. It helps to understand everything from X-rays to Nuclear Energy.

For further information on this interesting topic, visit the Three Types of Radioactive Decay Webpage or go here for an awesome song.

Resources“Periodic Table.” (2012). Retrieved 9 May 2012 from http://www.ptable.com/

“Radioactive Decay.” (2012). Retrieved 5 May 2012 from http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch23/modes.php#beta

“Three Types of Radioactive Decay.” (2012). Retrieved 6 May 2012 from http://library.thinkquest.org/3471/radiation_types_body.html

Tro, Nivaldo. Principles of Chemistry: A Molecular Approach (1st ed.). Upper Saddle River: Prentice Hall, 2009. Print.