Which of the following best describes how elements are arranged in the periodic table?

• A. Elements are grouped based on their physical state at room temperature.
• B. Elements are arranged in order of increasing atomic mass.
• C. Elements are arranged in order of increasing atomic number.
• D. Elements are arranged alphabetically by their chemical symbol.

Answer: (C)

Verified step by step guidance

1. Understand that the periodic table is a systematic arrangement of elements based on a fundamental property of atoms.
2. Recall that the atomic number of an element is the number of protons in its nucleus, which uniquely identifies each element.
3. Recognize that the modern periodic table arranges elements in order of increasing atomic number, not atomic mass or physical state.
4. Note that this arrangement leads to recurring (periodic) chemical properties, which is why elements in the same group (column) have similar characteristics.
5. Conclude that the best description is: Elements are arranged in order of increasing atomic number.