Mendeleev's Periodic Law states that:

Correct option is D

The correct answer is (D) the properties of elements are the periodic function of their atomic masses.

Explanation:

Mendeleev's Periodic Law, proposed by Dmitri Mendeleev in 1869, states that:

"The properties of elements are a periodic function of their atomic masses."

·         This means that when elements are arranged in order of increasing atomic mass, elements with similar properties recur at regular intervals or periods.

·         Mendeleev's periodic table was based on this law.

Key Points:

• Mendeleev's table organized elements into rows and columns based on their chemical and physical properties.
• He left gaps in his table for undiscovered elements and predicted their properties, which were later confirmed (e.g., gallium and germanium).