Which one is the wrong statement ?
(1) The energy of 2s orbital is less than the energy
of 2p orbital in case of Hydrogen like atoms
(2) de-Broglie's wavelength is given by λ = ``\frac {h}{mv}``
where m = mass of the particle, v = group velocity of the
particle.
(3) The uncertainty principle is ΔE X Δt ``\geq `` ``\frac{h} {4\pi}``
(4) Half filled and fully filled orbitals have greater
stability due to greater exchange energy, greater
symmetry and more balanced arrangement