Which of the following best describes how the periodic table is useful as a tool in chemistry?

• A. It shows the electron configuration for every possible ion.
• B. It lists all known compounds and their chemical reactions.
• C. It organizes elements based on their atomic number, allowing prediction of chemical properties and trends.
• D. It provides the exact mass of every atom in nature.

Answer: (C)

Verified step by step guidance

1. Understand that the periodic table is a systematic arrangement of elements based on their atomic number, which is the number of protons in an atom's nucleus.
2. Recognize that this organization groups elements with similar chemical properties into columns called groups or families, which helps predict how elements will behave chemically.
3. Note that the periodic table reveals trends in properties such as atomic radius, ionization energy, and electronegativity across periods (rows) and groups (columns).
4. Realize that while the periodic table provides valuable information about elements, it does not list electron configurations for every ion, nor does it list all compounds or exact atomic masses for every atom.
5. Conclude that the best description of the periodic table's usefulness is that it organizes elements by atomic number, enabling the prediction of chemical properties and trends.