The number of unpaired electron in Mn2+ ion is

The de-Broglie wavelength ($$\lambda$$) for electron (e), proton (p) and He2+ ion ($$\alpha$$) are in the following order. Speed of e, p and $$\alpha$...

In Bohr model of atom, radius of hydrogen atom in ground state is r1 and radius of He+ ion in ground state is r2. Which of the following is correct?...

Which one of the following is the correct set of four quantum numbers (n, 1, m, s) ?

The atomic masses of helium and neon are 4.0 and 20.0 amu respectively. The value of the de-Broglie wavelength of helium gas at $$-$$73$$^\circ$$C is ...

The maximum number of electrons in an atom in which the last electron filled has the quantum numbers n = 3, l = 2 and m = $$ - $$ 1 is

The radius of the first Bohr orbit of a hydrogen atom is 0.53 $$\times {10^-8}$$ cm. The velocity of the electron in the first Bohr orbit is

The number of unpaired electrons in the uranium (92U) atom is

The difference between orbital angular momentum of an electron in a 4f -orbital and another electron in a 4s-orbital is

Which one of the following electronic arrangements is absurd?

Which of the following electronic configuration is not possible?

The number of unpaired electrons in Ni (atomic number = 28) are

If the given four electronic configurations.(i) n = 4, l = 1(ii) n = 4, l = 0(iii) n = 3, l = 2(iv) n = 3, l = 1are arranged in order of increasing en...

Which of the following sets of quantum numbers represents the 19th electron of Cr(Z = 24) ?

Which one of the following corresponds to a photon of highest energy?