Question

Curium (Z=96) was formed by reacting Pu - 239 with alpha particles 42He. It has a half-life of 162 days

Answer 1

Answer:

When a nucleus captures a neutron, it often tries to correct for its neutron excess by beta decay, turning a neutron into a proton and thus creating an atom with atomic number Z increased by one unit. This commonly observed phenomenon suggests a way to create new elements of increased atomic number and thus to create ever more massive elements that are not found on Earth. Most of these elements are radioactive, with very short half-lives. However, theories of nuclear structure predict that at a certain atomic number, which is currently beyond present experimental limits, new long-lived nuclei can be created

Explanation

The most massive naturally occurring element on Earth is uranium (U), with a nucleus of 92 protons. In 1934, scientists started the search for more massive elements with 93 or more protons. They succeeded in 1940 when neptunium (Np, Z = 93) was synthesized at the University of California, Berkeley. Edwin McMillan and Philip Abelson observed Np while studying fission products produced in the bombardment of 238U with thermal neutrons. They found a radioactive reaction product that was not a fission product. This product was formed by the capture of a neutron to produce 239U, which subsequently b- decayed to 239Np via the reaction

239U + 1n Æ 239U (23.5 min) Æ 239Np (2.36 d),

Answer 2

Although your question is incomplete, you may be referring to:

Write the nuclear reactions involved in the synthesis of Curium (Z=96) formed by reacting Pu - 239 with alpha particles ⁴He₂. It has a half-life of 162 days

Given:

Curium is formed by reacting ²³⁹Pu with ⁴He₂.

Its half-life is 162 days.

To Find:

The nuclear reaction represents this situation.

Solution:

• There are 2 types of nuclear reactions:

1. Fission - When a large nucleus decays into smaller nuclei
2. Fusion - When many small nuclei combine to form a larger nucleus

• The given situation represents fusion.

It can be written as :

                       ²³⁹Pu₉₄ + ⁴He₂ ⇒ ²⁴²Cm₉₆ + ¹n₀

• In this reaction, Pu combines with an alpha particle to form the ²⁴²Cm isotope.
• To balance the number of nucleons, a neutron is also released.
• Both Pu and Cm are actinoids and radioactive. Thus, they show these types of nuclear decay reactions.

Hence, Pu fuses with an alpha-particle to form Cm and release a neutron.