Is it possible for the atom of an element to have one electron,one proton,and no neutron? If so,name the element.

Which of the following in the figure do not represent Bohr's model of an atom correctly?

$(a)$ Explain Bohr$-$Bury rules for the distribution of electrons into different shells.
$(b)$ Write the electronic configuration of an atom of sulphur. Also,draw a schematic diagram of its atom showing the distribution of electrons in its shells.

Mention the postulates of Niels Bohr put forth to overcome the objections raised against Rutherford's atomic model.

The electronic configuration of an element $X$ is $2, 8, 2$.
$(a)$ Find the number of electrons present in the atom of element $X$.
$(b)$ Write the atomic number.
$(c)$ Is this element $X$ a metal or a non-metal?
$(d)$ Find out the valency of the element $X$.

Give a brief account of the development of the presently accepted model of the atom with the contributions made by different scientists. Write two features of this atomic model.