Here's a fun party trick. How can you extinguish candles without touching them?
Put some vinegar in a jug and add in baking soda. This makes carbon dioxide that can be "poured" over the candles. And, poof! They extinguish.
The CO2 is heavier than air so not only does it stay in the jug but you can then pour it over the candles starving them of the oxygen they need to burn. It's fun, give it a try. Amaze your friends.