Question

The IUPAC symbol of an element is $'Ubn’$. The element belongs to
A) ${{1}^{st}}$ group and ${{7}^{th}}$ period
B) ${{17}^{th}}$ group, ${{7}^{th}}$ period
C) ${{2}^{nd}}$ group, ${{8}^{th}}$ period
D) ${{18}^{th}}$ group, ${{8}^{th}}$ period

Answer 1

Unbinilium is a hypothetical element of the periodic table. It is also known as eka radium. The atomic number of this element is $120$ . It has the symbol $Ubn$. The name Unbinilium and the symbol Ubn are temporary IUPAC names. This name and symbol exist until a permanent name is decided. It is expected to be an S-block element and an alkaline earth metal. It is the second element in the eighth period of the periodic table.

Complete step-by-step answer:
Rememberize the noble gas element in the periodic table, Likewise, $Ubn=120$ as the atomic number of Unbinilium is $120$. Unbinilium is $18$ element of group $2$ because the last group is $18$ and next is $2$ electrons added. So the group increases by factor of $2$.

Also, Atomic number of Unbinilium is $20$ . Which can be written as $18+2$, Here $18$ is element number and $2$is second group. Therefore, $2$group and it’s at $8$ period.

un	bi	hilium
1	2	0

This resembles its atomic number is $120$.

So the correct Option is (3) 2nd group, 8th period

Additional Information:
Also in Unbinilium all even-N isotopes from the neutron drip line to Ubn $385$ so they can form, either directly as material is ejected from a disintegrating neutron star. As a part of fission in fall from larger nuclides from directly-formed nuclide. So remember all isotopes in the band Ubn $384$ to Ubn $335$ can form the same way, although direct formation is unlikely at lower N.

One thing to keep in mind before solving that is no isotopes lighter than Ubn $335$ are likely to form. Beta decay chains with proper.

A value starting near the neutron drip line is terminated by fission $Z<120$. Note that termination requires rapid decay by fission. Nuclides whose half-lives are comparable with beta-emission half-lives do not terminate beta decay chains. It is improbable that neutron capture can form any Ubn isotope.

Note:
i) Unbinilium, Ubn, is the temporary name for element $120$, "Unbinilium", which addresses this element at length. This article focuses on topics isotopes far from $N=134$, which isotopes can actually form, and how long the element will be present.

ii) There are a large number of neutron-rich Ubn isotopes which can form. All will disappear within $1000$ sec after the event which led to their formation. There are also many isotopes near the $N=184$ and $N=196$ shell closures, but these cannot form, except by physicist-catalyzed reactions.

iii) While this element can exist in nature as a nuclear phenomenon, its chemistry exists only in the laboratory.

iv) Synthesis of Ubn has been reported, but not confirmed. It has been argued that Ubn may be the limit for current fusion-evaporation techniques.