The ionization energy of hydrogen atoms is 13.6 eV, the ionization energy of helium atom would be
13.6 eV
27. 2 eV
6.8 eV
54. 4 eV
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 a0 is the radius of the ground state orbit, m is the mass and e is the charge on the electron, ε0 is the vacuum permittivity, the speed of the electron is
Zero
The ground state energy H-atom is 13.6 eV. The energy needed to ionize H –atom from its second excited state is
1.51 eV
3.4 eV
12.1 eV
In a Rutherford scattering experiment when a projectile of charge Z1and mass M1 approaches a target nucleus of charge Z2 and Mass M2, the distance of closest approach is r0. The energy of the projectile is
directly proportional to M1 × M2
directly proportional to Z1 Z2
inversely proportional to Z1
directly proportional to Mass M1
In the Bohr model of the hydrogen atom, let R, V and E represent the radius of the orbit, the speed of electron and the total energy of the electron respectively.Which of the following quantity is proportional to the quantum number n?
E/V
R/E
VR
RE
When a hydrogen atom is raised from the ground state to an excited state
potential energy decreases and kinetic energy increases
potential energy increases and kinetic energy decreases
Both kinetic energy and potential energy decrease
Absorption spectrum
Hydrogen atom emits blue light when it changes from n = 4 energy level to n = 2 level. Which colour of light would the atom emit when it changes from n = 5 level to n = 2 level?
red
Yellow
violet
green
Hydrogen atoms are excited from ground state of the principal quantum number 4. Then the number of spectral lines observed will be
3
6
5
2
