Is it possible to have an element with atomic number 1.5 placed between hydrogen and helium?

Write the iupac name of element with atomic number 128

Write the iupac name of the element with atomic number 126

Give IUPAC name of an element having atomic number 106 is……… .

Write the electronic configuration of the element with atomic number 17. Indicate the valency of the element.

What valency will be shown by an element having atomic number 15 ?

What is the number of valence electrons in the atoms of an element having atomic number 13 ? Name the valence shell of this atom.

What valency will be shown by an element having atomic number 12 ?

What is the atomic number of hydrogen?

Is it possible to have interference between the waves produced by two violins? Why?

Two elements X and Y have atomic numbers 12 and 16 respectively. Write the electronic configuration for these elements. To which period of the modern perioidic table to these two elements belong? What type of bond will be formed between them and why?