How are elements arranged on the modern periodic table?

• A. By alphabetical order of element names
• B. By increasing atomic mass
• C. By the number of neutrons in the nucleus
• D. By increasing atomic number

Answer: (D)

Verified step by step guidance

1. Understand that the modern periodic table is organized based on a fundamental property of atoms called the atomic number, which is the number of protons in the nucleus of an atom.
2. Recall that the atomic number uniquely identifies each element and determines its chemical properties, unlike atomic mass or the number of neutrons, which can vary among isotopes.
3. Recognize that arranging elements by increasing atomic number results in a periodic pattern of chemical properties, which is the basis of the periodic law.
4. Note that earlier versions of the periodic table were arranged by increasing atomic mass, but this led to inconsistencies that were resolved by using atomic number instead.
5. Therefore, the correct way elements are arranged on the modern periodic table is by increasing atomic number, not by alphabetical order, atomic mass, or neutron number.