Arrange the following elements in decreasing order of their atomic size.

W, Re, Ir, Os

Question

Question

This question was previously asked in

AIIMS BSc NURSING 2023 Memory-Based Paper

Answer 1

CONCEPT:

Atomic Size

The atomic size of an element is determined by the distance from the nucleus to the outermost electron cloud.
Within a group in the periodic table, atomic size increases as you move down because additional electron shells are added.
Within a period, atomic size decreases from left to right due to the increasing nuclear charge, which pulls electrons closer to the nucleus.

EXPLANATION:

As we move across the period from left to right, the atomic size generally decreases.
Thus, the order of atomic size from largest to smallest among these elements is as follows:
- Tungsten (W) is the largest because it is the furthest to the left.
- Rhenium (Re) follows W.
- Osmium (Os) comes after Re.
- Iridium (Ir) is the smallest as it is the furthest to the right.

Therefore, the correct order of decreasing atomic size is: W > Re > Os > Ir.