How does the periodic table organize elements?

• A. By alphabetical order of element names
• B. By increasing atomic mass only
• C. By grouping elements based on their physical state at room temperature
• D. By increasing atomic number

Answer: (D)

Verified step by step guidance

1. Understand that the periodic table is primarily organized based on the atomic number of elements, which is the number of protons in the nucleus of an atom.
2. Recognize that arranging elements by increasing atomic number ensures that elements with similar chemical properties fall into the same columns or groups.
3. Note that while atomic mass was used in early versions of the periodic table, it does not consistently group elements with similar properties, so atomic number is the more accurate organizing principle.
4. Observe that the periodic table also groups elements into blocks and periods that reflect recurring trends in properties, such as metals, nonmetals, and metalloids, but these groupings are derived from atomic number order.
5. Conclude that the correct organization of the periodic table is by increasing atomic number, not by alphabetical order, atomic mass alone, or physical state at room temperature.