Question

The atomic number of the element with systematic name of Ununnilium is

• A. \(101\)
• B. \(109\)
• C. \(110\)
• D. \(111\)

Hint:

Remember the commonly used numerical roots: \[ \begin{aligned} 1 &\rightarrow \text{un} \\ 2 &\rightarrow \text{bi} \\ 3 &\rightarrow \text{tri} \\ 0 &\rightarrow \text{nil} \end{aligned} \] Ununnilium \(=\) Un + Un + Nil \(=\) \(110\).

Answer 1

The Correct Option is C

Concept: The IUPAC systematic nomenclature for newly discovered elements uses numerical roots corresponding to the digits of the atomic number. \[ \begin{aligned} 0 \quad &\rightarrow\quad \text{nil} \\ 1 \quad &\rightarrow\quad \text{un} \\ 2 \quad &\rightarrow\quad \text{bi} \\ 3 \quad &\rightarrow\quad \text{tri} \\ 4 \quad &\rightarrow\quad \text{quad} \\ 5 \quad &\rightarrow\quad \text{pent} \\ 6 \quad &\rightarrow\quad \text{hex} \\ 7 \quad &\rightarrow\quad \text{sept} \\ 8 \quad &\rightarrow\quad \text{oct} \\ 9 \quad &\rightarrow\quad \text{enn} \end{aligned} \] The suffix ium is added at the end of the name.

Step 1: Decode the systematic name. The name

Ununnilium can be divided as: \[\begin{aligned} \text{Un} \;-\; \text{Un} \;-\; \text{Nil} \;-\; \text{ium} \end{aligned}\] Using the IUPAC roots: \[\begin{aligned} \text{Un} &= 1 \\ \text{Un} &= 1 \\ \text{Nil} &= 0 \end{aligned}\]

Step 2: Determine the atomic number. Combining the digits, \[\begin{aligned} 110 \end{aligned}\] Therefore, the atomic number of Ununnilium is \[\begin{aligned} \boxed{110} \end{aligned}\] Hence, option \(\mathbf{(C)}\) is correct.