Modern Periodic Law And The Present Form Of The Periodic Table

The IUPAC name of element having atomic number 119 is "Ununennium". So its symbol is uue.

Electronic Configuration of Element X with atomic number 71 is . The Last electron will enter in orbital.

In the periodic table in the 7th period it is located and placed in the 11th group. Unununium is the IUPAC name given to the element Roentgenium. Roentgenium is a radioactive element and its isotopes are unstable in nature..

The Correct Answer is :Yellow

In the 4th period (K to Kr):
Atomic radius decreases across the period from left to right.
Largest atom: Alkali Metal Potassium (K).
Smallest atom: Halogen Bromine (Br). (Noble gases have larger van der Waals radii, so typically halogens are considered smallest in covalent radius trends).
Option (1) K and Br is the correct pair.