What Is The Wavelength Of The Light Emitted When The Electron In A Hydrogen Atom Undergoes Transition From An Energy Level With n = 4 To An Energy Level With n = 2? What Is The Colour Corresponding To This Wavelength? (Rydberg Constant = 109,677 Cm–1)   

Why Kaysons ?

Video lectures

Access over 500+ hours of video lectures 24*7, covering complete syllabus for JEE preparation.

Online Support

Practice over 30000+ questions starting from basic level to JEE advance level.

Live Doubt Clearing Session

Ask your doubts live everyday Join our live doubt clearing session conducted by our experts.

National Mock Tests

Give tests to analyze your progress and evaluate where you stand in terms of your JEE preparation.

Organized Learning

Proper planning to complete syllabus is the key to get a decent rank in JEE.

Test Series/Daily assignments

Give tests to analyze your progress and evaluate where you stand in terms of your JEE preparation.

SPEAK TO COUNSELLOR ? CLICK HERE

Question

What is the wavelength of the light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n = 4 to an energy level with n = 2? What is the colour corresponding to this wavelength? (Rydberg constant = 109,677 cm–1  

Solution

Correct option is

486 nm

 

 

The colour corresponding to this wavelength is blue

Testing

SIMILAR QUESTIONS

Q1

Calculate the uncertainty in the position of an electron if the uncertainty in its velocity is 5.7 × 105 m/sec (h = 6.6 × 10–34 kg m2 s–1, mass of the electron = 9.1×10–31 kg).

Q2

A golf ball has a mass of 40 g and a speed of 45 m/s. If the speed can be measured within accuracy of 2%, calculate the uncertainty in position.

Q3

 

If an electron is moving with a velocity 600 ms–1 which is accurate upto 0.005%, then calculate the uncertainty in its position. 

  (h = 6.63 × 10–34 Js, mass of electron = 9.1 × 10–31 kg) 

Q4

What is the transition in the hydrogen spectrum would have the same wavelength as the Balmer transition, n = 4 to n = 2 of He+ spectrum?

Q5

 

Calculate the energy required for the process

           He+ (g) → He2+ (g) + e   

The ionization energy for the H atom in the ground state is

 2.18 × 10–18 J atom–1.  

Q6

A 25 watt bulb emits monochromatic yellow light of wavelength of 0.57 μm. Calculate the rate of emission of quanta per second.

Q7

A certain particle carries 2.5 × 10–16 C of static electric charge. Calculate the number of electrons present in it.

Q8

An ion with mass number 37 possesses one unit of negative charge. If the ion contains 11.1% more neutrons then the electrons, find the symbol of the ion.    

Q9

An ion with mass number 56 contains 3 units of positive charge and 30.4% more neutrons than electrons. Assign the symbol to this ion.

Q10

Nitrogen laser produces a radiation at a wavelength of 337.1 nm. If the number of photons emitted is 5.6 × 1024, calculate the power of this laser.