The Great Plumbing Myth!

Plumbing Myth: Using Baking Soda and Vinegar to Clear a Blocked Drain.

You can find it everywhere…even government (cities mostly) entities promote the use of baking soda and vinegar to clear a blocked drain. The common claim is that the mixture will somehow magically change grease and sludge in the drain into soap and glycerin…freeing the blockage and leaving your drain fresh and sparkly clean! Is it true? Could this grade school science project be a complete replacement for all plumbers and commercial drain cleaners? Let us embark on a scientific journey to find the truth behind this popular mixture!

The key ingredient in vinegar is acetic acid (ethanoic acid). The amount of acetic acid in table vinegar is usually 4 to 8% in common table vinegar (mildly acidic). Baking soda is essentially sodium bicarbonate, an amphoteric compound that is slightly alkaline. The mixing of the two creates a reaction (rush of bubbles) that we all remember when we were in school (the erupting paper mache volcano?).

The two chemicals (acetic acid and sodium bicarbonate) when mixed form a new chemical called carbonic acid…commonly found in carbonated beverages. Carbonic acid in this form however is very unstable and immediately breaks down and turns into carbon dioxide (the bubbles) and water. After all the carbon dioxide escapes all that is left is sodium acetate and water. Sodium acetate is commonly found in foods we eat…such as salt-and-vinegar potato chips.

My point in this lengthy explanation? None of the chemicals…before, during, or after the mixing of the baking soda and vinegar will help clear a clogged drain. None of the acids is strong enough to break down hair or soap. Heck, we eat this stuff every day! So what could it be?

Commonly during chemical reactions heat is created…maybe, it is the heat. Our reaction is known as a neutralization reaction and they are exothermic in general. However, there are a couple conflicting processes going on in this reaction that may actually cause the temperature to DROP!

·       Evaporation of the liquid occurs as the carbon dioxide escapes (remember the bubbles?). Evaporation absorbs heat.

·       Rapidly expanding carbon dioxide cools as it expands…this is known as Joule-Thomson cooling. A visualization of this can be seen with the common computer-cleaning product, canned air. Hold the nozzle open and see how cold it gets…freezing…very quickly!

Ok, so it is not the baking soda, the vinegar, the chemical process, any chemical, or the heat that will open a clogged drain. I am sorry to report that the science simply does not support the use of these household products as effective in clearing a clogged drain. If anything, it may clog it further as the remaining solids from the chemical reaction could form a grey sludge.

But wait!!!! There is still a great use for this in your kitchen…including your drains!

Baking Soda and white vinegar is great in sanitizing and getting rid of odors. It can help keep clear drains clean and keep them smelling fresh. In tests run at Virginia Polytechnic Institute and State University, Pairing the two killed virtually all Salmonella, Shigella, or E.Coli Bacteria on heavily contaminated food and surfaces when used in this fashion, making these two natural cooking ingredients more effective at killing these potentially lethal bacteria than chlorine bleach or any commercially available kitchen cleaner.

My suggestion…1/2 cup of baking soda, add ½ cup of vinegar in your drain (that is not currently clogged). Place the stopper on the drain if applicable. Wait 30 minutes or so and rinse down the drain with boiling water. Wait a few more minutes and flush completely with hot water from the tap to rinse down any remaining solids. This should help keep your drain clear and keep it smelling fresh.