Question

Once the compounds are separated and purified in the separations experiment they are then identified. Answer the following true/false questions regarding this part of the experiment:         
TrueFalse The carboxylic acid unknown once separated from the neutral unknown is identified by its melting point.
TrueFalse The neutral unknown once separated from the carboxylic acid is identified by IR spectroscopy.

It is important to consider some experimental complications in the identification of compounds in the separations experiment. Answer the following true/false questions relating to this:         
TrueFalse If there is water in the neutral unknown sample, there will be a broad OH peak in the IR spectrum.
TrueFalse If MTBE is not completely removed from the neutral unknown, there will be peaks in for C-H(sp² in the IR.
TrueFalse If the carboxylic acid is not completely removed from the neutral unknown, there will be peaks from the carboxyl group in the IR.
TrueFalse If there is water in the neutral unknown sample, it can be removed by adding more Na₂SO₄.
TrueFalse If MTBE is not completely removed from the neutral unknown, there will be peaks in for C-H(sp³ in the IR.
TrueFalse If your melting point for your unknown acid is broad, it is because the your crystals may be still wet.

Answer 1

True. The acid unknown is identified by its melting point
True. The neutral unknown is also identified by its melting point and IR spectroscopy

True. The broad peak appears around 3400 1/cm in the IR spectra
False. in MTBE, there is no sp2 hybridized carbon and hence no peak for C-H (sp2)
True. Depending on the quantity of acid left in the neutral compound, there will be peak for acid.
True. water can be removed by adding Na2SO4 and also by keeping in the desiccator.
True. peak for C-H (sp3) appears in IR spectra.
True. Presence water in acid reduces the crystallinity and hence a broad melting point range results.