Potential Difference of Electrons and Balmer Series

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Electrons bombarding hydrogen must be accelerated through a specific potential difference to emit the first line of the Balmer series. This occurs when an electron collides with a hydrogen atom, imparting enough kinetic energy to elevate an electron to a higher energy level. The energy gained by the electron is equal to eU, where U is the potential difference. The Balmer series lines correspond to transitions to the second energy level (n=2), with the first transition being from n=3 to n=2. Understanding the energy levels of the hydrogen atom is essential to calculate the required potential difference.
CollectiveRocker
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A beam of electrons bombards a sample of hydrogen. Through what potential difference must the electrons have been accelerated if the first line of the Balmer series is to be emitted? How does this even begin?
 
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CollectiveRocker said:
A beam of electrons bombards a sample of hydrogen. Through what potential difference must the electrons have been accelerated if the first line of the Balmer series is to be emitted? How does this even begin?

The electron collides with the hydrogen atom and kicks one electron out to a higher level, supposed it has enough kinetic energy, equal to or higher than the difference of energy between those electron levels.

The electron gains kinetic energy equal to eU by flying through a potential difference U.

The spectrum lines of Balmer series correspond to transition onto the second level (n=2) The first of them is from n=3 to n=2.

Find the formula for the energy levels of hydrogen atom. Combine these all together and you get the answer. :smile:

ehild
 
Please explain more.
 
CollectiveRocker said:
Please explain more.

I would but I can not write a book here. What is what you know? You certainly have a textbook. What does it write about the energy levels of Hydrogen atom, about spectrum lines and about the Balmer series in the emission spectrum of Hydrogen?

ehild
 
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