IR spectra for un unknown substance?

IR spectra for un unknown substance? Topic: Sample on how to write a report
June 16, 2019 / By Jaye
Question: I have received a few IR spectra of un unkown compound, which is a solid probe.The IRs were taken on both surfaces: glossy and opaque. The peaks of each face of the probe are almost the same for each type of absorbtion, just the amount of energy absorbed is different(for ex.: at 1238cm-1 for one face I have 85%(glossy face) of absorbance and for the other 80%(opaque face)). What could cause this difference of absorbance for the same functional group? The two spectra, often, are overlaped, the shape of the peak is the same, but also I have a difference of 5-10% in absorbance. Around 2350cm-1 on one spectra I have a weak (double peak) absorbtion and on another spectra I have a peak with the same shape but seen in a mirror; instead to have a peak downward, I have upward. Please help me.... For more information, I could send you a pdf copy of the spectra.
Best Answer

Best Answers: IR spectra for un unknown substance?

Gair Gair | 10 days ago
There will be a bit more scattering with the opaque sample with respect to the glossy sample. I suspect that your spectra are written in transmission mode, since you report the values as percentage values, which would make sense if the opaque sample is scattering more light (i.e., less light is making it back to the spectrometer.) Absorbence is slightly different, and typically not reported for IR spectra. That peak at 2350 wavenumbers is carbon dioxide. It's usually present in most IR spectra, and it can appear positive or negative depending on how the air in the room has changed since you took the blank. Most programs have a collection mode to cancel out the CO2 signal so you don't have to bother with it later.
👍 128 | 👎 10
Did you like the answer? IR spectra for un unknown substance? Share with your friends

We found more questions related to the topic: Sample on how to write a report

Gair Originally Answered: How to identify an unknown substance if you know the mass and the amount of heat to raise it to a certain temp?
Homework due in another hour, eh? It's so 'gold' when you procrastinate and come here at the last possible minute! Edit: It's gold. Specific heat of tungsten is 133 J/(kg-k). Simple math fail? I gave the answer the first time around :/
Gair Originally Answered: How to identify an unknown substance if you know the mass and the amount of heat to raise it to a certain temp?
definite. Take a lime kiln as an occasion. Calcium Carbonate is heated to generate Calcium Oxide and Carbon Dioxide. The Carbon Dioxide leaves as a gas, lowering the quantity of mass recent interior the forged state.

Gair Originally Answered: Looking for maiden name of Julie Cullifer. Married name unknown. Residence unknown help find her PLEASE?
Genealogy is about researching the records of our ancestors and the records we research are old records, so from 70 -100 years ago as those are the records that are availble for searching................ living people have privacy rights which means in the main you can only search what THEY make available, such as telephone directories, electoral registers, on social media websites and they are generally what the information is from for people search websites ................. so you are very limited with not having much information and posting on a world wide forum means you are blanket targetting the World.............( I am answering from Ireland) your question will remain on this 1st page for maybe a day and only live for about 4 days for people to answers...so......... All I can suggest is written above this website has several links you can try, but you have to be realistic without a full name you have little chance http://familytimeline.webs.com/adoptionl... except who else knew he,? Ask them! Check out HS year books, there are some online. Have you gone to the library and looked at the newspapers for that area to find a report of the accident? In case it givesyou further clues with hers or others names you could search.searching FB is possibly you best bet and on your FB page making it clear who you are looking for so she or someone who knows her can easily contact you............. hope you find her

If you have your own answer to the question sample on how to write a report, then you can write your own version, using the form below for an extended answer.