Editing Floating Soap Bubbles (section)

== Why This Works ==

===Short Explanation===
In this demonstration, we are looking at the difference in density of various gases. ''Density'' is when you divide the mass of something by the volume it takes up. For liquids and gases, a more dense liquid or gas will sink below a less dense one, letting the less dense gas or liquid "float" on top. This is the effect we are seeing with the bubbles in our fish tank!

We first had baking soda and vinegar react in the fish tank, which produces carbon dioxide gas (CO<sub>2</sub>). CO<sub>2</sub> is a heavier gas in our atmosphere, and will sink below the other gases like oxygen and nitrogen in still air. This means that, when the reaction happens in the fish tank, the CO<sub>2</sub> will stay inside the fish tank and push the other gases out. This is why we see the bubbles floating inside the tank when we blow them in as well! The bubbles have an air mix of CO<sub>2</sub>, oxygen, nitrogen, argon, and even some water vapor inside of them. This mix of gases is lighter than pure CO<sub>2</sub>, which allows the bubble to float inside the fish tank!

===Full Explanation===
The ''Density'' of a substance is equal to the mass of the substance divided by the volume. With fluids such as gases and liquids, the less dense fluids will float atop the more dense ones if left undisturbed. The density of a fluid correlates with the molar mass of the fluid. This means that if we know the molar mass of an element or compound, then we can predict if it will float above or sink below other elements and compounds that are in the same state of matter.

We had vinegar and baking soda react inside of this container to produce carbon dioxide. CO<sub>2</sub> has a high molecular mass compared to the other gases that are in our atmosphere, so it will sink and stay within the fish tank after the reaction. When we start blowing bubbles above the container, they are filled with air from our lungs, which is a mixture of water vapor, nitrogen, oxygen, argon and carbon dioxide. This air mixture is about as dense as the air around, but the bubble it is inside of is slightly heavier than the air, so it will sink into the fish tank. Once inside, it will float atop the denser CO<sub>2</sub>.
{| class="wikitable" style="color:black; background-color:#ddd; text-align: left; margin-left: auto; float:right"
| '''Gases'''
| '''Molar Mass'''
| '''Density'''
|-
| Water Vapor (H<sub>2</sub>O)
| 16 g/mol
| .804 g/L
|-
| Air (Sea Level)
| ~28 g/mol
| 1.23 g/L
|-
| Nitrogen (N<sub>2</sub>)
| 28 g/mol
| 1.25 g/L
|-
| Oxygen (O<sub>2</sub>)
| 32 g/mol
| 1.43 g/L
|-
| Argon (Ar<sub>2</sub>)
| 36 g/mol
| 1.78 g/L
|-
| Carbon Dioxide (CO<sub>2</sub>)
| 44 g/mol
| 1.98 g/L
|}

This table is provided so to look at how the density of a compound or element correlates with the molar mass. Notably, water vapor has the lowest molar mass, and with that it has a substantially lower density. This is part of the reason why we have clouds; humid air rises much faster than dry air, since the water vapor in the air is lowering the overall density, and therefore drier air will sink below it. This humid air will continue to rise until it reaches the ''Homosphere'' (Troposhere, Mesosphere and Stratosphere), where it will condense and freeze into clouds! It is also worth noting that the Air density is listed as being at sea level. This is because the density of the air around us can change based on where we are on the earth. Air density becomes lower as you go higher into the atmosphere, and at high altitudes it can become hard to breathe because the air is not dense enough. The opposite is also true; if you went into a cave that goes deep inside the earth, it will become harder to breathe because the air is ''too'' dense!