Interpret the temporary systematic element name

The name Unnilunium is formed using the IUPAC temporary naming system for undiscovered/newly named elements.

The roots correspond to digits as follows:

• un $\to 1$
• nil $\to 0$
• un $\to 1$
• suffix ium is added at the end

Construct the atomic number

So, Unnilunium corresponds to the digit sequence:

$1\,0\,1$

Hence the atomic number is:

$101$

Final Answer

The atomic number of Unnilunium is:

$\boxed{101}$

Comparison with stored correct answer

• Derived answer: $101$
• Stored correct answer: $101$

These match.