Why does baking soda + vinegar work?

Pour a little vinegar on a small pile of baking soda & watch what happens. The mixture is also great for removing coffee, tea and a variety of other stains.

Vinegar in general is a good inexpensive cleaner.

@stanleybmanly Yes, I know that the mixture foams and bubbles, but isn’t that just the two substances neutralizing each other? How can that dissolve stains and drain clogs?

I have no data so I’m making a guess.
When the two mix they produce a lot of CO2 bubbles at fairly high pressure. If the mix gets into small cracks in the clog maybe the targeted expansion of the bubbles helps break the blockage up so water pressure can finish the job.

It is precisely the foaming action that makes this a good combination.

As @LuckyGuy suggests, you’re in essence fracking your own drain.

“Scrubbing bubbles”

31 uses

It’s true that an acid and a base will neutralize each other. But neutralization is a process, and that process is neither instant nor tranquil. The turbulence of the reaction loosens up whatever is clogging the drain, and the release of carbon dioxide pushes it along. If the mixture seeps into the clog at all, that can also help as the reaction expands outwards (sort of exploding the clog from within). The actual dissociation and recombination of atoms is more or less confined to the acid and base themselves. It’s the physical agitation caused by the reaction that unclogs the drain.

As the others have said, it’s the physical movement of particles in the drain that does the unclogging. The unclogging process is mechanical, not chemical.

But it’s the chemical reaction that causes the physical reaction.

Of course. But the reason the OP is asking the question is that a chemical reaction is clearly taking place, but does not appear to involve the contents of the clog. His instinct about that is correct. Regardless of what is happening chemically between the vinegar and the baking soda, they interact with the clog only mechanically.

Great answers, everybody! Thank you so much!
Some people also recommend adding salt to the mix. How does that help?

Baking soda is alkaline. Vinegar is acidic. Be sure that you have good ventilation when you use it.

I’ve never heard of adding salt, but there’s already sodium in the bicarb, so maybe the release of the chlorine makes it more effective when you add salt. Once again, be sure you have good ventilation.

I did a search for the chemical reaction for mixing vinegar and baking soda and found NaHCO3 + HC2H3O2 → NaC2H3O2 + H2O + CO2. In line with what has been said, it would be the pressure from the released carbon dioxide that does the work. The reaction also releases energy, which would heat the CO2 and cause it to expand more quickly,