Navigate

The wavelength of the first line of Lymasn series for hydrogen atom is equal

The wavelength of the first line of Lyman series for hydrogen atom is equal to that of the second line of Balmer series for a hydrogen like ion. The atomic number Z of hydrogen like ion is

Options

(a) 3
(b) 4
(c) 1
(d) 2

Correct Answer:

2

Explanation:

For first line of Lyman series of hydrogen
hc/λ₁ = Rhc (1/1² – 1/2²)
For second line of Balmer series of hydrogen like on
hc/λ₂ = Z²Rhc (1/2² – 1/4²)
By eq. λ₁ = λ₂
(1/1 – 1/2) = Z² (1/4 – 1/16) or Z = 2

AIPMT2011
admin:

Related Questions

  1. The potential energy of particle in a force field is U = A/r² – b/r, where A and B
  2. A transformer is used to light a 100 W and 110 V lamp from a 220 V mains.
  3. The internal energy change in a system that has absorbed 2 kcals of heat
  4. A photoelectric surface is illuminated successively by monochromatic light of wavelength
  5. A particle moves along a circle of radius 20/π m with constant tangential acceleration