Which system did Dmitri Mendeleev use to arrange the elements in his periodic table according to their properties?

• A. By alphabetical order
• B. By increasing atomic number
• C. By increasing atomic mass
• D. By electron configuration

Answer: (C)

Verified step by step guidance

1. Recall the historical context of Dmitri Mendeleev's periodic table, which was developed before the discovery of the atomic number.
2. Understand that Mendeleev arranged elements based on a property that was measurable at the time: atomic mass.
3. Recognize that Mendeleev noticed patterns in the properties of elements when they were ordered by increasing atomic mass, which allowed him to predict the existence and properties of undiscovered elements.
4. Note that the arrangement by atomic number came later, after the discovery of the proton and the concept of atomic number was established.
5. Conclude that the system Mendeleev used to arrange elements was by increasing atomic mass, not by alphabetical order, atomic number, or electron configuration.