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### Understanding the Rydberg Formula

Posted: **Sat Oct 14, 2017 8:34 pm**

by **Hena Sihota 1L**

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?

### Re: Understanding the Rydberg Formula

Posted: **Sat Oct 14, 2017 8:42 pm**

by **AtreyiMitra2L**

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.

### Re: Understanding the Rydberg Formula

Posted: **Sat Oct 14, 2017 8:54 pm**

by **404995677**

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

### Re: Understanding the Rydberg Formula [ENDORSED]

Posted: **Sat Oct 14, 2017 10:05 pm**

by **Chem_Mod**

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.

### Re: Understanding the Rydberg Formula

Posted: **Sun Oct 15, 2017 12:36 am**

by **Iris Shim 1E**

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

### Re: Understanding the Rydberg Formula

Posted: **Sun Oct 15, 2017 12:36 pm**

by **Haocheng Zhang 2A**

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.

### Re: Understanding the Rydberg Formula

Posted: **Sun Oct 15, 2017 4:18 pm**

by **Justin Lai 1C**

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