Look at the table of radioactive isotypes below.

Question

Isotype Type of Decay
Uranium-238 Alpha
Nickel-63 Beta
Iodine-131 Beta
Radium-226 Alpha

With the help of a periodic table, predict the element that forms in each case.
I'm confused by this. Am I suppose to research each of the isotypes and find out what element they have or compare it to the elements that are in the periodic table?

Answer 1

U238 for example has 92 protons and therefore 146 neutrons

It loses an alpha particle which is a helium nucleus, 2 protons and 2 neutrons

so
NOW we have an element with
92 - 2 = 90 protons
238 - 4 = 234 atomic mass ignoring E = mc^2

What has 90 protons?
Th Thorium 232 is usual isotope but we have Th234 at present

Answer 2

Note from wikioedia:
Uranium-238 - Wikipedia, the free encyclopedia
en.wikipedia.org/wiki/Uranium-238
Wikipedia
Jump to Radioactivity and decay - [edit]. 238U radiates alpha-particles and decays
**** (by way of thorium-234 ****** and protactinium-234) into uranium-234. 234U ...