[natalie_2006]

Hi
I'm confused with this question:
What experimental evidence requires that the emission of energy by an atom be quantized?

I know quantize means to split or sub divide energy.  Would experiments using light, and showing how the light can be spilt by seeing the various colours?

Thanks
Natalie  

[Mitch]

Quantize doesn't mean that.

[Donaldson Tan]

Quantise means to limit the possible values of (a magnitude or quantity) to a discrete set of values by quantum mechanical rules. This means the value of the energy of emission is not a continuous function.

An example of a quantized function is sin(x) - 1 = 0. x can only take up odd multiples of Pi/2. the range for the value of x is not continous. Hence, we can say that x is quantised.

[natalie_2006]

ok... but it's a chemistry question that was on a test and I just didn't know how to answer it... can you help me to answer it?

[Donaldson Tan]

the lines in the absorption spectra of elements correspond to the energy differences between the energy levels of the atomic orbitals. these lines serve as experimental evidence that the energy of each atomic orbital is quantised. therefore, when an electron in an atomic orbital demote to an orbital of lower energy level, the energy emitted must correspond to the energy difference between the former and the new atomic orbital. this means the energy of atomic emission must be quantised.

[natalie_2006]

Thanks so much.... I really had no clue, as stupid as that makes me sound..

[Donaldson Tan]

you must first understand the concept of being quantised.

imagine there are 5 poles apart.

the distance between the 1st and 2nd pole is 2m.

the distance between the 1st and 3rd pole is 3m.

the distance between the 1st and 4th pole is 4m.

the distance between the 1st and 5th pole is 5m.

imagine u are a runner. you can only run from one pole to another. imagine you start at the first pole. this means you can only run to 2nd, 3rd, 4th or 5th pole. this means the distance u run must be 2m, 3m, 4m or 5m. The distance you run is not a continuous, eg. you cannot run 2.53m

[natalie_2006]

So basically the question is asking why is it important to have the values for the energy released from atoms?  like what has it allowed us to find...  so it's able to find out about wavelengths; such as their length and amplitude

and does it have to do with the electromagnetic field?

[Donaldson Tan]

So basically the question is asking why is it important to have the values for the energy released from atoms?  like what has it allowed us to find...  so it's able to find out about wavelengths; such as their length and amplitude

This I agree, but I can't comment on the part on electromagnetic fields. Let's hope someone can answer you on that.