Who among the following scientist proposed that "the physical and chemical properties of the elements are periodic functions of their atomic numbers"?

Option 2 : Henry Moseley

The correct answer is Henry Moseley.

• Henry Moseley was an English physicist known for his Moseley's law which is the basis of the modern Periodic Table.
  • Henry Moseley observed regularities in the characteristic X-ray spectra of the elements. A plot frequency of X-rays emitted against atomic number gave a straight line and the plot of the frequency of X-rays emitted vs atomic mass was not a straight line.
  • Based on the above experiment he proposed that "the physical and chemical properties of the elements are periodic functions of their atomic numbers".

• Dmitri Mendeleev was a Russian scientist known for his contribution to the development of the Periodic Law and to construct his Periodic Table of elements.  
  • According to the Periodic Law of Mendeleev, the properties of the elements are a periodic function of their atomic weights.
  • The element with atomic number 101 named Mendelevium, in the honor of Dmitri Mendeleev.
  • He is also known as the Father of the periodic table.
• John Alexander Newlands was a British chemist known for his contribution to the development of the Periodic Table and Law of Octaves.
  • John Alexander Newlands in 1865 profounded the Law of Octaves. He arranged the elements in increasing order of their atomic weights and noted that every eighth element had properties similar to the first element.
• Johann Dobereiner was a German chemist known for his contribution to the development of Periodic Table and Periodic Law known as Law of Triads.
  • Johann Dobereiner in the early 1800s was the first to consider the idea of trends among properties of elements.
  • He noted a similarity among the physical and chemical properties of several groups of three elements (Triads).
  • In each case, he noticed that the middle element of each of the Triads had an atomic weight about halfway between the atomic weights of the other two Also the properties of the middle element were in between those of the other two members. This was known as the Law of Triads.