Heavy nuclie are unstable due to large repulsive forces between large number of protons in the nucleus .
Why is a heavy nucleus unstable?
The presence of too many protons and neutrons in heavier nuclei will upset the balance and binding energy of nuclear force , which make the nucleus unstable. Such an unstable nucleus achieves the balance by giving off the neutron and proton via radioactive decay.
Why are heavy nuclei relatively less stable?
Heavier nuclei are less stable—that’s something we all learned in school. Adding more nucleons (protons and neutrons) makes atoms more likely to break apart . ... The number of protons (labeled Z) determines the chemical element, and the number of neutrons (written as N) determines the isotope.
What makes heavy elements unstable?
Many of the elements heavier than lead have nuclei so large that they are fairly unstable. Due to the instability, over time they eject a neutron or proton, or a neutron in the nucleus decays into a proton and electron . This is called radioactive decay, since the original nucleus is “decaying” into a more stable one.
Why do heavier elements tend to be more unstable?
If you have more neutrons than protons, then there will be more strong force present to counteract the repulsive forces between protons .
Why are all elements above 82 unstable?
When the mass number of the atom is greater than 82, the atoms are not stable because of the level of binding energy. The atom splits because of the force of repulsion between the particles and the new elements are formed as they reach the new configuration which is stable. ...
Why are large nuclei Z 83 typically unstable?
Atoms with very low atomic numbers have about the same number of neutrons and protons; as Z gets larger, however, stable nuclei will have more neutrons than protons. ... Nuclei with more than 83 protons are all unstable , and will eventually break up into smaller pieces; this is known as radioactivity.
Which element has a heavier nuclei?
The heaviest naturally stable element is uranium , but over the years physicists have used accelerators to synthesize larger, heavier elements. In 2006, physicists in the United States and Russia created element 118.
Which nucleus is most stable?
Nickel-62 is an isotope of nickel having 28 protons and 34 neutrons. It is a stable isotope, with the highest binding energy per nucleon of any known nuclide (8.7945 MeV).
Why do heavy nuclei undergo alpha decay?
Alpha decay occurs most often in massive nuclei that have too large a proton to neutron ratio . ... Alpha radiation reduces the ratio of protons to neutrons in the parent nucleus, bringing it to a more stable configuration. Many nuclei more massive than lead decay by this method.
What is the largest stable element?
The periodic table could be considered to end at the largest stable element, lead (atomic number 82). All elements with higher atomic numbers have unstable nuclei, because the assembled protons become too large for the strong nuclear force to hold together.
Which is the most unstable element?
Characteristics. Francium is one of the most unstable of the naturally occurring elements: its longest-lived isotope, francium-223, has a half-life of only 22 minutes.
What is the heaviest element ever?
The heaviest element found in any appreciable amount in nature is uranium , atomic number 92. (The atomic number refers to the number of protons in an atom’s nucleus.)
Why are heavier isotopes more radioactive?
The stability of a nucleus depends upon the number of protons and neutrons are nearly equal, then the nucleus is stable. ... As a result, the nuclei of heavier elements are unstable, and show radioactivity. The heavier elements show radioactivity because the nuclei of these elements contain more neutrons than protons.
What is the most stable proton to neutron ratio?
Hydrogen-1 (N/Z ratio = 0) and helium-3 (N/Z ratio = 0.5) are the only stable isotopes with neutron–proton ratio under one. Uranium-238 has the highest N/Z ratio of any primordial nuclide at 1.587, while lead-208 has the highest N/Z ratio of any known stable isotope at 1.537.
Why do atoms have unstable nuclei?
When the atoms of an element have extra neutrons or protons it creates extra energy in the nucleus and causes the atom to become unbalanced or unstable. Whether radioactive elements can become stable and if so, how. The unstable nucleus of radioactive atoms emit radiation. ... This process is called radioactive decay.
