Which of the following best describes how the periodic table is organized?

• A. By increasing atomic number, with elements arranged in periods and groups based on similar chemical properties
• B. By increasing atomic mass, with elements grouped solely by physical state
• C. Randomly, with no specific order or classification
• D. Alphabetically by element name, with no regard to chemical properties

Answer: (A)

Verified step by step guidance

1. Understand that the periodic table is a systematic arrangement of elements based on their atomic structure and properties.
2. Recall that the modern periodic table is organized primarily by increasing atomic number, which is the number of protons in an atom's nucleus.
3. Recognize that elements are arranged in rows called periods, where each period corresponds to the filling of a principal electron shell.
4. Identify that elements are also arranged in columns called groups or families, where elements share similar chemical properties due to having the same number of valence electrons.
5. Conclude that the best description of the periodic table's organization is by increasing atomic number, with elements arranged in periods and groups based on similar chemical properties.