2 experiments with CO2

Mix baking soda and vinegar in zip lock bags and watch the bags fill with CO2.

'Pour' the CO2 into a plastic pail and lower a lit match into it (by hand). The match goes out when it passes into the CO2.

If you can get a strip of magnesium, ignite that and lower that into CO2 - it won't go out but will instead strip the oxygen off the CO2, leaving carbon dust floating in the pail.

CAUTION: It sparks brightly and makes loud popping noises. It is best to add the magnesium outside because of this