Question

Draw potassium sulfate as if it was a covalent compound.

Assuming the above structure, which bonds do you expect to show up in the IR?

Please explain how you figure this out... :/

Answer 1

In the spectrum you would spect to have a band around 500-600cm-1, because at that wavelength is when the bond can bend. This number its extract from the tables of IR vibrations, this are standard tables because many studies has been made, and a group or bond always vibrate at the same energy with little variation cause by the groups around the one we are studing.

Because this is ionic compound the K+ doesn´t show, and the structure with the negative charge will have resonance in it, so its to spect that the pick won´t be to big.