I don't know if a complete field is easier, but some topics definitely are.http://www.chemicalforums.com/index.php?topic=84190.msg305518#msg305518
fill a hot-water bottle with a paraffin (or a wax) instead, melt it. More capacity, constant comfortable temperature, easy, useful. Find and check some convenient means to melt the paraffin.http://www.chemicalforums.com/index.php?topic=75605.0
collect a few alkanes, freeze them to liquid nitrogen temp, measure carefully the density to confirm or infirm the usual odd/even theory. Quickly done, experiments not completely trivial, little theory, make human knowledge progress.https://www.scienceforums.net/topic/79154-produce-ice-faster/
very useful, can bring BIG money, possibly too vast for a student's project, so extract a subproject from it. Like: find a source of cold air, drop the water with simple means, observe if clear ice forms quickly.http://www.chemicalforums.com/index.php?topic=69134.msg249525#msg249525
purify Ag from Cu and others by vacuum distillation. Economically useful. No trivial setup, nor very difficult.http://www.chemicalforums.com/index.php?topic=90705.0
compact plastic parts made by 3D-printing. Reasonably easy, useful.https://www.chemicalforums.com/index.php?topic=56069.msg376196#msg376196
Biodegradable lubricants and hydraulic fluids.
Measure the effect of geminal amines N-C-N on the enthalpy of formation, as compared with homologue amines C-C-N and alkanes C-C-C. Buy adamantane and hexamethyl tetramine "hexamine", burn them in a calorimetric bomb, measure accurately, deduce the effect. Repeat with bought CN(C)CN(C)C, CN(C)CC(C)C and CC(C)CC(C)C. Existing data seems inconsistent, and I've seen nothing about the effect of geminal amines, but didn't check the best sources neither.http://www.chemicalforums.com/index.php?topic=46407.msg325514#msg325514
Measure heats of formation of imines (if not available in the literature)https://www.chemicalforums.com/index.php?topic=56069.msg349723#msg349723
make farnesane from caparrapi oil or nerolidol. Hydrogenation could be slightly dangerous. Make a lab demo.https://www.chemicalforums.com/index.php?topic=107038.0
Try to add Mo to electroformed Ni or NiCo, observe the properties, mechanical and others. Ni is easily electrodeposited, Mo has nearly the same redox potential as Ni and Co, which supposedly helps.https://www.chemicalforums.com/index.php?topic=56069.msg376204#msg376204
Easy reaction, but harsh conditions and stinky. Check what products and mixes are liquid, comment interesting properties.https://www.scienceforums.net/topic/111316-woodwind-materials/?do=findComment&comment=1072342
Find electrically conductive ink, measure the resistance of a line, observe it varies by deformation. Hammer the line, check if the resistance is more constant.
If you want more difficult topics, just tell.