What is the primary significance of the periodic table of elements?

• A. It groups elements according to their physical state at room temperature.
• B. It arranges elements by their mass number.
• C. It lists elements in alphabetical order for easy reference.
• D. It organizes elements based on their atomic number and recurring chemical properties.

Answer: (D)

Verified step by step guidance

1. Understand that the periodic table is a systematic arrangement of elements that helps chemists predict properties and behaviors of elements.
2. Recognize that the primary organizing principle of the periodic table is the atomic number, which is the number of protons in an element's nucleus.
3. Know that elements are arranged in order of increasing atomic number from left to right and top to bottom.
4. Observe that elements with similar chemical properties are grouped into columns called groups or families, which show recurring or periodic trends.
5. Conclude that the periodic table's significance lies in its ability to organize elements based on atomic number and recurring chemical properties, rather than physical state, mass number, or alphabetical order.