Atomic Spectra RT

Radius of first orbit of Hydrogen atom is equal to

• 5.3 A⁰

• 0.53 A⁰

• 53 A⁰

• 5.53 A⁰

The ratio of the kinetic energy and the total energy of the electron in the hydrogen atom, according to Bohr’s theory, is

• 1: - 1

• 1:1

• 1:2

• 1: - 2

Atomic hydrogen is excited to the 8^th energy level. How many spectral lines can be observed in spectrum?

• 8

• 16

• 28

• 64

The ratio of minimum to maximum wavelength in Balmer series is:

• 5 : 9

• 5 : 36

• 1 : 4

• 3 : 4

The transitions of inner shell electrons in heavy atoms give rise to the emission of:

• γ –rays

• x – rays

• β – rays

• None of these

Meta stable states have life time of the order of:

• 10^–8 sec

• 10^–6 sec

• 10^–3 sec

• 10^–10 sec

Highly intense, monochromatic and coherent beam of light obtained by stimulating atoms of a suitable material is called

• X- rays

• Laser

• Ultraviolet rays

• γ-rays

The shortest wavelength of the Lyman series is approximately

• 1020 A⁰

• 920 A⁰

• 820 A⁰

• 720 A⁰

In the production of laser beam for each incident photon, we will have two photons going:

• In the same direction

• In opposite direction

• At right angle to each other

• In arbitrary direction

Most commonly used type of gas laser is:

• Helium-Neon

• Carbon dioxide

• Argon ion

• All of above