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

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

Answer: (B)

Verified step by step guidance

1. Understand that the periodic table is a systematic arrangement of elements, not random or alphabetical.
2. Recall that elements are arranged in order of increasing atomic number, which is the number of protons in an atom's nucleus.
3. Recognize that the table is organized into periods (rows) and groups (columns), where elements in the same group share similar chemical properties.
4. Note that while atomic mass was historically used, the modern periodic table is based on atomic number to reflect periodic trends accurately.
5. Conclude that the best description is: elements are arranged by increasing atomic number, with periods and groups reflecting similar chemical behaviors.