Its hard to predict experiments but these ones seem to come up most often....
* To show a plant produces starch during photosynthesis (it came up in 2015 - unlikely)
* Titration (Its likely to come up)
* To show the presence of CO2 in air (it came up in 2015 - unlikely)
* Chromatography (highly likely)
* Distillation (likely)
* Preparation of O2 (likely)
Other possible experiments...
* Seed Germination
* Conditions necessary for rusting
* To show CO2 is more dense than air
I hope this helps :) (good luck)