How were the positions of cobalt and nickel resolved in the Modern Periodic Table?
✅ Answer: Modern Periodic Table is based on the atomic number. Thus Cobalt (27) is placed before Nickel (28).
How were the positions of isotopes of various elements decided in the Modern Periodic Table?
✅ Answer: Isotopes have same atomic number. So they are placed in the same group.
Is it possible to have an element with the atomic number 1.5 placed between hydrogen and helium?
✅ Answer: No. Because the atomic number is a whole number.
Where do you think should hydrogen be placed in the Modern Periodic Table?
✅ Answer: The position of hydrogen in the Modern Periodic Table is correct.