CBSE Physics Atomic Physics Test Online

1. The ionization energy of the electron in the hydrogen atom in its ground state is 13.6 eV. The emit radiations of 6 wavelength. Maximum wavelength of emitted radiation corresponds to the transition between ?

2. When hydrogen atom is in its excited level its radius is ?

3. Ionization potential of hydrogen atom is 13.6 eV. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. According to Bohr's theory, the spectral lines emitted by hydrogen will be ?

4. In Rutherford scattering experiment, what will be the correct angle for a α-scattering for an impact parameter, b = 0 ?

5. Hydrogen atoms are excited from ground state of the principle quantum number 4. Then the number of spectral lines observed will be ?

6. Which source is associated with a line emission spectrum ?

7. The radius of hydrogen atom is its ground state is 5.3 x 10^-11 m. After collision with an electron it is found to have a radi7us of 21.2 x 10^-11m. What is the principal quantum number n of the final state of the atom ?

8. The total energy of electron in the ground state of hydrogen atom is -13.6 eV. The kinetic energy of an electron in the first excited state is ?

9. The spectrum obtained form a sodium vapour lamp is an example of ?

10. Energy E of a hydrogen atom with principal quantum number n is given by E = -13.6/n² eV. The energy of a photon ejected when the electron jumps from n = 3 state to n = 2 state of hydrogen, is approximately ?

11. Bohr model of atoms ?

12. The energy of ground electronic state of hydrogen atom is -13.6 eV. The energy of the first excited state will be ?

13. In a Rutherford scattering experiment when a projectile of charge Z₁ and mass M₁ approaches a target nucleus of charge Z₂ and mass M₂ the distance of closest approach is r_°. This energy of the projectile is ?

14. The total energy of an electron is the first excited state of hydrogen is about - 3.4 eV. Its kinetic energy in this state is ?

15. The ionisation energy of hydrogen atom is 13.6. Following Bohr's theory, the energy corresponding to a transition between 3rd and 4th orbit is ?

16. When electron jumps form n = 4 to n = 2 orbit, we get ?

17. In the Bohr's model of a hydrogen atom, the centripetal force is furnished by the Coulomb attraction between  the proton and the electron. If α_°is the radius of the ground state orbit, m is the mass and e is the charge on the electron, ε_° is the vacuum permittivity, the speed of the electron is ?

18. The ground state energy of H-atom is 13.6 eV. The energy needed to ionize H-atom from its second exited state ?

19. Consider an electron in the nth orbit of a hydrogen atom in the Bohr model. The circumference of the orbit can be expressed in terms of de-Broglie wavelength λ of that electron as ?

20. The ground state energy of hydrogen atom is -13.6 eV. When its electron is in the first excited state, its excitation energy is ?

21. Energy A, B, C, of a certain atom correspond to increasing values of energy ei, E_A < E_B< E_C. If λ1, λ2, λ3 are the wavelengths of radiation corresponding to the transitions C to B, B to A and C to A respectively, which of the following relation is correct ?

22. The valence electron in alkali metal is a ?

23. Which of the following transitions gives photon of maximum energy ?

24. To explain his theory, Bohr used ?

25. The ionisation energy of hydrogen atom is 13.6 eV, the ionisation energy of helium atom would be ?

26. When a hydrogen atom is raised from the ground state to an excited state ?

27. In terms of Bohr radius α_°, the radius of the second Bohr orbit of a hydrogen atom is given by ?