Domestic Chemistry

I had left our oven for a few weeks without cleaning,, so I set about it this morning.

We use Olive Oil for roast vegetables, and unfortunately its splashes bake hard on the [enamel] panels of the oven.

After several hours of pretty fruitless hard-labour, I decided to search for advice

Google found several recommendations for the use of a paste made from Baking Soda and Vinegar … So I tried that, and it works amazingly well !!

So my question is: Can someone please explain the chemistry ?

MichaelG.

No, but I have 2 approaches to cleaning ovens

1. don't bother, the food doesn't actually touch it
2. buy a pyrolytic oven, the it cleans itself.

I haven't got enough years eft to waste them cleaning ovens!

You get carbon dioxide gas, water and sodium acetate, we used to put it in a bottle to create a volcano, or to unclog a drain.

Thor

As much physics as Chemistry I think! Baking Soda (Sodium Bicarbonate) is abrasive, and Acetic Acid attacks Grease, so rubbing the combination into the muck will break up the surface. The acid also reacts with the Bicarbonate to produce bubbles of Carbon Dioxide, many of which will be inside the cracks, crevices and pores of the grease. Although the bubbles are tiny, the pressure exerted as they emerge is enormous. Very difficult to stop a chemical reaction with pressure, as this ex-gun barrel shows!

Dave

Mixing vinegar and bicarbonate of soda while visually impressive does not make a good cleaner. Try them on their own next time. Mixing them basically makes water and CO2 with possibly a tiny amount of sodium nitrate (lye) but it's insignificant.
At least one commercial oven cleaner is mainly bicarbonate of soda paste. It works well

Robert G8RPI.

I'll admit I see no logic to mixing the two together. If it worked for you then fine.

When I needed to clean my oven I found reference to using just baking soda and set too with a will..and ended up with a god-awful mess of caked baking soda on the oven surfaces that took ages to clean off - particularly out of the creases and around the seals. Since then I've just trained myself to wipe the oven out after any usage with eco washing up liquid solution.

pgk

.

Thanks for that, Thor

So … does that cocktail react in any peculiar way with Olive Oil ‘lacquer’ ?

MichaelG.

Just for clarity … Messy as it is: the process is orders-of-magnitude more effective than anything else I tried [and much safer to use than the dreaded Mr Muscle].

MichaelG.

... and here's me believing for years that lye is sodium hydroxide.

Hi Michael,

Using baking soda alone to scrub your oven will clean it as it is abrasive, as Dave says the carbon dioxide gas made when mixed with vinegar helps mix and agitate to move dirt particles. Better explanations:

***Link***

***Link***

Thor

cif can be pretty impressive against baked grease

Thanks to Dave and Thor … I am reminded of a previous thread on this forum, about micro-bubbles generated in canine toothpaste.

I am happy to believe that the underlying process is generally similar.

MichaelG.

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Ref. https://www.model-engineer.co.uk/forums/postings.asp?th=144313&p=1

Edited By Michael Gilligan on 13/04/2022 19:36:14

I'd like to learn how to make sodium nitrate from acetic acid.

George

Lakeland Ovenmate for me

I have seen dish washer tabs rubbed onto the surfaces clean the glass doors.

I think you're right to be happy in that belief Michael. I use a 15% solution of sodium hydroxide with a bit of surfactant myself. It works well, but it's messy and even at that concentration it takes several hours for the chemistry to work. I shall certainly try the vinegar/bicarb method!

On the chemistry front I'm pretty skeptical about claims that vinegar 'attacks' grease in a chemical way. It's certainly true that grease can be broken down by dilute acid (acid hydrolysis of esters), but I doubt that the reaction is significant in cleaning an oven. Possibly it has some mild solvent action?

On canine tooth cleaning - I don't think I reported back on my plan to use the ultrasonic toothbrush for rust removal. Pure funk I'm afraid. The risk of domestic disharmony if it went wrong was too great. I expect it would work though. Might be good for cleaning ovens (slowly) as well.

Robin

Edited By Robin Graham on 14/04/2022 01:03:16

Try Borax Substitute (sodium sesquicarbonate), mix it to a paste with water, rub it in and leave a while. Not as good as Sodium Hydroxide, but a lot safer.

I had a problem with a sticky yellow stain from cooking oil on my plastic mixer bowl, it was removed in minutes. It also removes the sticky yellow that builds up around the cooker.

Well said Duncan - with you all the way. There are other similar things e.g. cutting lawns, cleaning cars, the possibilities are endless!

There is one other method, my wife gets a guy in to clean the oven, I do my best to keep the glass top clean.

Martin P

That's what I was hinting at when I said the answer was as much to do with physics as chemistry. Dilute Acetic Acid isn't like Caustic Soda, which attacks fats aggressively; Vinegar only has a mild dissolving effect. Simply splashing vinegar on a dirty oven won't get it clean. It's important that the Bicarbonate / Acid mix be a paste, in which the Bicarbonate and Acid are slowly reacting to produce micro-bubbles, AND there are plenty of sharp Bicarbonate crystals to act as an Abrasive, AND there's enough fluid to penetrate tiny cracks and crevices, AND the paste is rubbed in enthusiastically by the operator. Works in much the same way as soapy Brillo-pad, except the Brillo pad abrades with steel-wool, soap breaks up the fat and there are no micro-bubbles.

Cleaning an oven with a solution of Sodium Acetate made by carefully neutralising Sodium Bicarbonate with Vinegar is a waste of time. It's not reactive or abrasive and there are no micro-bubbles.

Caustic Soda paste, made with water, can be splashed on and left. The alkali breaks fats up, so the operator can leave the oven to soak and wash the whole lot off with water a few hours later. Sodium Bicarbonate would do the same but take a lot longer.

Anyone tried Isopropyl alcohol? Apart from the cost, fumes, and fire hazard I think it might work well. Ditto petrol...

Dave