Using only the periodic table, arrange each set of atoms in order of increasing radius: (a) Cs, Se, Te (b) S, Si, Sr (c) P, Po, Pb.

Verified step by step guidance

1. Identify the positions of Sulfur (S), Silicon (Si), and Strontium (Sr) on the periodic table. Note their groups (columns) and periods (rows).
2. Understand that atomic radius generally increases as you move down a group because additional electron shells are added, making the atom larger.
3. Recognize that atomic radius generally decreases as you move from left to right across a period due to the increase in nuclear charge which pulls the electron cloud closer to the nucleus.
4. Compare the positions of S, Si, and Sr. Sulfur and Silicon are in the same period with Sulfur being to the right of Silicon, indicating Sulfur has a smaller atomic radius than Silicon. Strontium is located in a period below both Sulfur and Silicon, suggesting it has a larger atomic radius than both due to being in a lower period.
5. Arrange the atoms in order of increasing atomic radius based on the trends: Sulfur (S), Silicon (Si), Strontium (Sr).

Key Concepts

Atomic Radius

Atomic radius is a measure of the size of an atom, typically defined as the distance from the nucleus to the outermost electron shell. It 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.

Periodic Trends

Periodic trends refer to predictable patterns in the properties of elements as you move across or down the periodic table. Key trends include atomic radius, ionization energy, and electronegativity. Understanding these trends helps in predicting the behavior of elements and their relative sizes based on their position in the periodic table.

Group and Period Classification

Elements in the periodic table are organized into groups (columns) and periods (rows). Elements in the same group often exhibit similar chemical properties and trends, while properties change across a period. For example, sulfur (S) is in Group 16, silicon (Si) in Group 14, and strontium (Sr) in Group 2, which influences their atomic radii and helps in arranging them by size.