How can you figure out what happens when an element
undergoes alpha and beta decay?

Question:  How can you figure out what happens when an element undergoes alpha and beta decay?


Answer:
Just like with a lot of chemical processes, we need to follow the law of conservation of mass to find our answer.

Alpha particles are helium nuclei, meaning that they have two neutrons and two protons.  When an atom gives off an alpha particle, all we need to do is decrease the mass symbol (top left) by four and decrease the atomic number by two.  As a result, we can see that when 238U undergoes alpha decay, we get the following reaction:

238 U --> 234Th + 4He

Beta particles are electrons, meaning that they have no mass (that you can account for in this process, anyway) and an atomic number of -1 (because the charge of an electron is -1).  As a result, if an atom gives off an alpha particle, the mass number doesn't change but the atomic number increases by one.  As a result, we can see that when  238U undergoes beta decay, we get the following reaction:
238U --> 238Np + e-



Do you have a question for Mr. Guch?  Email him at misterguch@chemfiesta.com .