Baking Soda and Vinegar
Baking Soda and Vinegar
[Ponytail is standing behind Science Girl who has one hand up. They are looking at a table with a model volcano.] Science Girl: My science project is a baking soda and vinegar volcano!
[A larger frame that includes Megan who stands to the right. Ponytail is a little further back and Science Girl has taken her hand down. The baking soda volcano erupts in a small upwards explosion.] Ponytail: Why do people make these? It isn't really even a science project. It doesn't teach anything about- Volcano: Foom!
[Smaller frame again. Ponytail has moved closer to the table, Science Girl moves around the table to the right, pointing at the volcano while Megan walks closer. The "lava" flows down the volcano on both sides.] Science Girl: See how the baking soda and vinegar mix with mud and ice to form deadly flowing lahars?
[Zoom in on Science Girls head close to the stream of lava going down the lower part of the volcano's right slope.] Science Girl: You can see the tiny cars trying to flee. Science Girl: Whoops! Too slow.
[Zoom in on Ponytail.] Ponytail: Um. This is a bit grim. Science Girl (off panel): Learning!
[Science Girl stand to the right of the table looking at the now still volcano. Shaky lines surround a sound effect written over the top of this slim frame:] Rumble
[Back to showing all three as before. Science Girl lift a finger in the air.] Science Girl: And now we're learning that this volcano is an offshoot of a vinegar hotspot rising from deep within the earth. Science Girl: Annnd...
[Science Girl turns away from the table looking right as a loud noise can be heard off-panel, depicted in white text on a wavy black bubble:] Boooom
[Megan has walked over to a window to the right. It has the blinds drawn down. She opens a hole in the blinds by pulling down in the middle. It is dark outside. The other two are outside the frame to the left.] Science Girl (off panel): The baking soda supervolcano erupts, injecting clouds of salt into the stratosphere. Megan: Why is it getting dark outside? Science Girl (off panel): Learning is fun!
[We see Science Girl standing close to the table, of which only the right leg can be seen. She holds up a tablet with a graph showing a rising trend. The other two are both out of the frame.] Science Girl: Sunlight dims. The earth cools. Summer frosts form. Crops die. We check the markets. Grain prices are rising. Megan (off panel): I want to stop learning now. Science Girl: Soon, we all will.

In popular fiction (and maybe in part in fact) the " Baking Soda and Vinegar " volcano is often a staple image of the science nerd at the science fair (see example here ), unless all the science nerds are doing real imaginative science and the student(s) with the volcano exhibit are dragging out the old hackneyed stereotype. It may also be age-dependent, this being something that is relatively advanced science for the lower grades but rather a childish experiment in the hands of older students.
Ponytail is about to point out any one of a number of flaws with the trope. For one thing, while the project may exhibit interesting physical phenomena of the sort that some scientists study, the project itself doesn't actually teach anything about the scientific method. Actual science fairs are usually intended to teach students about the scientific method by exercising it firsthand: subjecting hypotheses to appropriately rigorous experimentation, and reporting on the results. The cliché volcano exhibit doesn't teach any of this, and may instead reinforce the idea that science is about cool explosions and not a system of inquiry. Further, the exhibit doesn't (usually) actually demonstrate anything about real volcanic activity: it is relatively simple chemistry involving the reaction of acetic acid in vinegar and sodium bicarbonate in baking soda to produce sodium acetate and (notably) a vigorous froth made up of bubbles of carbon dioxide. It is often dressed up to look more impressive, such as by using dye or other additives to make the 'eruption' look more 'realistic,' but it often fails to replicate important features of actual volcanic eruptions, such as the flow of lava, associated seismic events or the collapse of part of the volcanic crater. Most people doing soda volcano projects don't even explain what's happening.
Science Girl has made a little more of her volcano, however, as it seems to go beyond simple chemistry. The model replicates many of the dangers (aside from the pure lava) of a volcano, and appears to have been given scaled-down vehicles (not visible in the comic) trying (and failing) to escape the dangers of the resultant mud-flows (a.k.a. lahars in professional terminology) being modeled. Ponytail contradicts her early reaction by also not liking the more realistic model, although it is the carnage she dislikes, not that it has more correct details of the eruption itself.
Even more, this is not an isolated 'model volcano' but a vinegar-powered representation of a geological 'hot spot', such as with the islands of Hawaii, in which the spot moves with respect to the Earth's crust (or vice-versa) and generates a new volcano some way off.  Despite this model being supported on a table, it appears that the 'project' extends some way beyond that and has somehow contrived further eruptions away from the table, the room and probably even the building.
The 'project' seems to be turning into a very thorough model of a much larger geological process (a Supervolcano like the one under Yellowstone ) and destined to produce a very real volcanic winter .  Where a magma-powered volcano could produce vast clouds of dust, preventing the sun's energy from warming the Earth, in this case it's the airborne salt (probably sodium acetate) from the chemical reaction that appears to be in danger of causing crop failure.  There's no mention of the corresponding environmental effects of the vast amounts of carbon dioxide (and/or aqueous carbonic acid) necessarily released in proportion to the ejected salt (presumably itself not left in solution).
It is especially troubling that the child even mentions that her model volcano is an offshoot of a baking soda super volcano. Supervolcanoes are massive volcanoes, far larger than even those on the list of Decade Volcanoes (mentioned in the title text), whose eruption would likely trigger species-level extinction events comparable to the dinosaur extinction. Humanity can only hope the child is exaggerating in her description, but the symptoms witnessed by the adult looking out the window suggest otherwise. Campi Flegrei is actually a real life example of her project.
When someone (presumably the dark haired woman) says she wants to stop learning, Science Girl grimly states that "Soon, we all will", alluding to their impending doom.
Randall has mentioned supervolcanoes before in 1053: Ten Thousand (title text) and 1159: Countdown , making it a recurring interest of his. The volcano Mount Doom was depicted to the far left in the game 1608: Hoverboard released a week before this comic. It may not be a supervolcano, but quite potent anyway... Later this comic was directly referenced in the seventh panel of 1714: Volcano Types , where it is up to the reader to decide it this is Science Girl's model people or what happens outside on her supervolcano.
In the title text the student expects extra credit for getting her model volcano added to the Decade Volcanoes list, a list maintained by International Association of Volcanology and Chemistry of the Earth's Interior of the world's most dangerous volcanoes (currently 16). It is either an absurd notion or a very troubling achievement that a science fair project could achieve the threat level posed by the likes of Mount Vesuvius (which destroyed ancient Pompeii in Italy, and threatens modern-day Naples in the same manner), Mount Rainier (whose lahars could potentially destroy parts of Seattle) or Mauna Loa (which could create a massive landslide, triggering a major tsunami that would threaten all of Hawaii). But if the volcano erupting outside is scaled down to match the scale of her original model volcano, at least that means that it was only a "local" volcano event and not a supervolcano event that she created, so it would only doom the local area.
[Ponytail is standing behind Science Girl who has one hand up. They are looking at a table with a model volcano.] Science Girl: My science project is a baking soda and vinegar volcano!
[A larger frame that includes Megan who stands to the right. Ponytail is a little further back and Science Girl has taken her hand down. The baking soda volcano erupts in a small upwards explosion.] Ponytail: Why do people make these? It isn't really even a science project. It doesn't teach anything about- Volcano: Foom!
[Smaller frame again. Ponytail has moved closer to the table, Science Girl moves around the table to the right, pointing at the volcano while Megan walks closer. The "lava" flows down the volcano on both sides.] Science Girl: See how the baking soda and vinegar mix with mud and ice to form deadly flowing lahars?
[Zoom in on Science Girls head close to the stream of lava going down the lower part of the volcano's right slope.] Science Girl: You can see the tiny cars trying to flee. Science Girl: Whoops! Too slow.
[Zoom in on Ponytail.] Ponytail: Um. This is a bit grim. Science Girl (off panel): Learning!
[Science Girl stand to the right of the table looking at the now still volcano. Shaky lines surround a sound effect written over the top of this slim frame:] Rumble
[Back to showing all three as before. Science Girl lift a finger in the air.] Science Girl: And now we're learning that this volcano is an offshoot of a vinegar hotspot rising from deep within the earth. Science Girl: Annnd...
[Science Girl turns away from the table looking right as a loud noise can be heard off-panel, depicted in white text on a wavy black bubble:] Boooom
[Megan has walked over to a window to the right. It has the blinds drawn down. She opens a hole in the blinds by pulling down in the middle. It is dark outside. The other two are outside the frame to the left.] Science Girl (off panel): The baking soda supervolcano erupts, injecting clouds of salt into the stratosphere. Megan: Why is it getting dark outside? Science Girl (off panel): Learning is fun!
[We see Science Girl standing close to the table, of which only the right leg can be seen. She holds up a tablet with a graph showing a rising trend. The other two are both out of the frame.] Science Girl: Sunlight dims. The earth cools. Summer frosts form. Crops die. We check the markets. Grain prices are rising. Megan (off panel): I want to stop learning now. Science Girl: Soon, we all will.
