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. In a n-p-n transistor about 10¹⁰ electrons enter the emitter in 2 μs,
  2. If vectors A=cos wti + sin wtj and B= cos wt/2 i + sin wt/2 j are functions of time,
  3. A body is thrown vertically upward in air when air resistance is taken into account
  4. A rocket is fired upward from the earth surface such that it creates an acceleration
  5. A round disc of moment of inertia i₂ about its axis perpendicular to its plane