Skip to main content
Ch.7 - Periodic Properties of the Elements
Chapter 7, Problem 34

Arrange each of the following sets of atoms and ions, in order of increasing size: (a) Pb, Pb2+, Pb4+

Verified Solution

Video duration:
2m
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Atomic Radius

The atomic radius is a measure of the size of an atom, typically defined as the distance from the nucleus to the outermost electron shell. Atomic size generally increases down a group in the periodic table due to the addition of electron shells, while it decreases across a period from left to right due to increased nuclear charge, which pulls electrons closer to the nucleus.
Recommended video:
Guided course
02:02
Atomic Radius

Ionic Radius

The ionic radius refers to the size of an ion in a crystal lattice. Cations (positively charged ions) are smaller than their neutral atoms because the loss of electrons reduces electron-electron repulsion and allows the remaining electrons to be pulled closer to the nucleus. Conversely, anions (negatively charged ions) are larger than their neutral atoms due to increased electron-electron repulsion from the added electrons.
Recommended video:

Charge and Size Relationship

The charge of an ion significantly affects its size. For a given element, as the positive charge increases (e.g., from Pb to Pb2+ to Pb4+), the ionic radius decreases due to the increased effective nuclear charge acting on the remaining electrons. This results in a stronger attraction between the nucleus and the electrons, pulling them closer and reducing the overall size of the ion.
Recommended video:
Guided course
01:53
Formal Charge