Structure of At...

In what region(s) of the spectrum does this series occur? Visible region is from $$360$$ to $$780\ nm$$.

The time period of revolving in the third orbit of $$Li^{2+}$$ ion is $$x$$ second. The time period of revolution in the second orbit of $$He^+$$ ion should be

The energy of an electron in the first Bohr orbit for $$He^+$$ ion is $$-54.4eV.$$ Which one of the following is a possible excited state for electron in Bohr orbit of $$He^+$$ ion ?

The atom/ion is

In the Bohr's model of the hydrogen atom, let r, v and E represent the orbit radius, speed of the electron, respectively. Which of the following relation is proportional to the orbit number $$n$$? 

The energy emitted when electron of $$1.0\ g$$ atom of hydrogen undergo transition giving the spectral lines of lowest energy in visible region of its atomic spectra is 

The spectrum of helium is similar to:

The d orbital(s) involved in the formation of the complex(C) will be?

All of the following possess complete d-shells except: 

Bohr model of an atom could not account for :