Understanding the Rydberg Formula  [ENDORSED]


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Hena Sihota 1L
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Understanding the Rydberg Formula

Postby Hena Sihota 1L » Sat Oct 14, 2017 8:34 pm

When using the Rydberg formula to calculate the frequency and you get a negative value do you omit the negative sign for the final answer because frequency can't be negative? Or do you leave the negative sign because it indicates that the electron went from a higher energy level to a lower energy level?

AtreyiMitra2L
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Re: Understanding the Rydberg Formula

Postby AtreyiMitra2L » Sat Oct 14, 2017 8:42 pm

Frequency should never be negative. Consequently, the negative sign should be omitted. The energy, however, still should be negative. It is this value that shows that the electron went from a higher energy level to a lower energy level.

404995677
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Re: Understanding the Rydberg Formula

Postby 404995677 » Sat Oct 14, 2017 8:54 pm

I am also confused about the reason of the negative symbol in the equation.

Chem_Mod
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Re: Understanding the Rydberg Formula  [ENDORSED]

Postby Chem_Mod » Sat Oct 14, 2017 10:05 pm

The negative indicates that a photon is emitted. The electron is losing that energy, so the energy is negative. If it is positive, the electron gains energy and the photon is absorbed.

Iris Shim 1E
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Re: Understanding the Rydberg Formula

Postby Iris Shim 1E » Sun Oct 15, 2017 12:36 am

The negative sign means the electron's energy has decreased, and the energy is released as electromagnetic radiation.

Haocheng Zhang 2A
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Re: Understanding the Rydberg Formula

Postby Haocheng Zhang 2A » Sun Oct 15, 2017 12:36 pm

When using the Rydberg formula to calculate the frequency, we actually calculate the energy gap between two energy levels. Getting a positive value means the electron gains energy and it needs absorb light. Getting a negative value means the electron loses energy and emits light. Whether the light is absorbed or emitted, the energy of light must be a positive value, so frequency should always be positive.

Justin Lai 1C
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Re: Understanding the Rydberg Formula

Postby Justin Lai 1C » Sun Oct 15, 2017 4:18 pm

Frequency should always be positive so the negative sign is used when the change between initial and final is negative


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