[kaslee]

For an independent project that we're working on, we are grinding together 3 different starting materials (2 solids, 1 liquid) to form a solid product and we're monitoring progress with TLC using a 3:1 hexane/ethyl acetate solvent. A have quite a few questions...

initially, i was thinking of dissolving the solids with ethyl acetate for spotting. only problem is one of my starting materials and the product itself does not dissolve in it. i have tried a variety of other solvents (water, ethanol, hexane, etc.) to no avail.  In the end, we just had to use DMSO.
-----> to keep it uniform, should i just use DMSO to dissolve all my solids?

again, one of my starting materials is a liquid (benzaldehyde), we spotted it on the plate in its pure form, and it ended up being a streak, even forming like a cloud-like horizontal shape right where it ended.
------> Could this be because we used 100% concentration of the liquid?  how exactly do i go about spotting a pure liquid substance?( since the rest of the solid compounds were basically diluted to form a 1% solution for spotting)

Thank you

[rolnor]

You need to dilute benzaldehyde. Also this is volatile so its not so good running TLC.
Have you tried DMF instead of DMSO? I guess you need to dry the TLC-plate before running and then its easier to dry spots if you use DMF.