Arrange in decreasing order, the energy of $2 s$ orbital in the following atoms $\mathrm{H}, \mathrm{Li}, \mathrm{Na}$ and K .
The number of radial nodes in 3s and 2p respectiely are
The uncertainty in the momentum of an electron is $$2.0 \times 10^{-8} \mathrm{~kg} \mathrm{~ms}^{-1}$$. The uncertainty in its position will be
In which of the following photoelectric effect is observed?
An electron in H-atom in its ground state absorbs 1.50 times as much as energy as the minimum required for its escape $$(13.6 \mathrm{~eV})$$ from the atom. Thus, KE given to emitted electron is
What is the total number of electrons that can have the values $$n=2, l=1, s=1 / 2$$ in the electronic configuration $$1 s^2 2 s^2 2 p^3$$ ?
Calculate the wavelength associated with an electron moving with a velocity of $$10^6 \mathrm{~m} / \mathrm{s}$$ (mass of electron $$=9.1 \times 10^{-31} \mathrm{~kg}, h=6.6 \times 10^{-34} \mathrm{~kg} \mathrm{~m}^2 \mathrm{~s}^{-1}$$ )
Which of the following pairs is not correctly matched?