Question

An element with IUPAC symbol ‘Unq' belongs to period number 'x' and group number 'y'.

The sum x + y is ___.

Answer 1

11

Answer 2

The IUPAC symbol ‘Unq' represents the element with atomic number 104 (Un-nil-quad-ium).

1. Period Number (x): Elements with atomic numbers from 87 to 118 are in the 7th period. Since the atomic number is 104, $x = 7$.

2. Group Number (y): The electronic configuration of element 104 is $[Rn] 5f^{14} 6d^2 7s^2$. It is a d-block element in the 7th period. The group number for d-block elements is the sum of electrons in the outermost $ns$ subshell and the penultimate $(n-1)d$ subshell. For element 104, $n=7$. The number of electrons in $7s$ is 2, and the number of electrons in $6d$ is 2. Therefore, $y = 2 + 2 = 4$.

3. Sum x + y: $x + y = 7 + 4 = 11$.

The sum $x + y$ is 11.