If the following element undergoes alpha decay, which element does it change into?
234/90th
a
Uranium (U)
b
Francium (Fr)
c
Radium (Ra)
d
Radon (Rn)
c) Radium (Ra)
Alpha decay is the process in which an atomic nucleus releases an alpha particle, which consists of two protons and two neutrons. The atomic number decreases by 2, and the mass number decreases by 4.
Given that the element undergoing alpha decay is 234/90th, we need to subtract 2 from the atomic number (90) and 4 from the mass number (234).
Therefore, after alpha decay, the element changes into:
c) Radium (Ra) with an atomic number of 88 and a mass number of 230.
To determine which element the given element (234/90Th) changes into during alpha decay, we need to understand how alpha decay works.
Alpha decay is a type of radioactive decay where an atomic nucleus emits an alpha particle, which consists of two protons and two neutrons. As a result of this process, the parent element loses two protons and two neutrons, causing its atomic number (the number of protons) to decrease by 2 and its atomic mass (the number of protons plus neutrons) to decrease by 4.
In this case, the parent element is 234/90Th, which means it has an atomic number of 90 (protons) and an atomic mass of 234 (protons + neutrons). After alpha decay, the parent element will change into a new element.
To determine the new element, we subtract 2 from the atomic number (90 - 2 = 88) and subtract 4 from the atomic mass (234 - 4 = 230). Therefore, the new element is 230/88Ra, which corresponds to Radium (Ra) in the periodic table.
So, the correct answer is c) Radium (Ra).