Which of the following best explains why the periodic table is considered a useful tool in chemistry?

• A. It organizes elements based on their atomic number, revealing periodic trends in properties.
• B. It provides detailed instructions for chemical reactions.
• C. It groups elements solely by their color and physical state.
• D. It lists elements in alphabetical order for easy reference.

Answer: (A)

Verified step by step guidance

1. Understand the purpose of the periodic table: it is designed to organize elements in a way that reveals patterns and relationships among their properties.
2. Recall that elements in the periodic table are arranged by increasing atomic number, which is the number of protons in an atom's nucleus.
3. Recognize that this arrangement leads to periodic trends, such as variations in atomic radius, ionization energy, and electronegativity, which repeat in a predictable manner across periods and groups.
4. Evaluate the incorrect options: the periodic table does not provide detailed instructions for chemical reactions, nor does it group elements solely by color or physical state, and it is not arranged alphabetically.
5. Conclude that the best explanation for the usefulness of the periodic table is that it organizes elements based on their atomic number, revealing periodic trends in their properties.