Consider the unbalanced equation for the oxidation butane
C4H8+6O2 CO2+H2O

It will appear as o2(g) as a reactant 

For lesson: cameras, plant presses, newspaper, paper towels, clip boards, pencils, calculators, field guides, metric measuring tapes, paper, transect squares, colored pencils, ph meters, light meters, computers, etc.for extension: baggies for soil samples collecting, distilled water, hand shovels, beakers, boiled rice, microscopes, well microscope slides or regular microscope slides with cover slips

Answerheavy water or deuterium oxide.

That would be d bud have you answer it yet