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
The energy required to excite hydrogen atom from n = 1 to n = 2 state is 10.2 eV. What is the wavelength emitted when it returns to ground state?
1020 × 10-10 m
1220 × 10-10 m
1320 × 10-10 m
920 × 10-10 m
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
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
The ionization energy of hydrogen atom is 13.6 eV. Following Bohr’s theory, the energy corresponding to a transition between 3rd and 4th orbit is
3.40 eV
1.51 eV
0.85 eV
0.66 eV
The Bohr model of atoms
Assumes that the angular momentum of electrons is quantized
Uses Einstein’s photoelectric equationÂ
Predict continuous emission spectra for atoms
Predicts the same emission spectra for all types of atoms
When hydrogen atom is in its first excited level, its radius is
Four times, its ground sate radius
Twice, its ground state radius
Same as its ground state radius
Half of its ground state radius
The ionization energy of Hydrogen atom is 13.6 eV, the ionization energy of Helium atom would be
13.6 eV
27. 2 eV
6.8 eV
54. 4 eV
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
3.4 eV
1.7 eV
The spectrum obtained from a sodium vapour lamp is an example of
Band spectrum
Continuous spectrum
Emission spectrum
Absorption spectrum
