Apologies first and foremost but I have virtually no scientific background, experience, or knowledge for that matter and I’m not able to convincingly debunk a claim I read yesterday on another forum.
A poster purported that a tomato mixed with sugar would produce a substance capable “peeling sheets of paint” off of a car. Instantly, I called BS but I couldn’t tell him or anyone else why it wouldn’t work.
So, can anyone tell me exactly why tomatoes and sugar mixed together won’t produce something that can wreak havoc on someone’s paint job?
I tried that route. He “saw” it work so of course it works. I’m just a bit angered I can’t put together some sort of response that will remove all doubt from him and everyone else so that these idiots don’t go trying this to someone’s car.
Considering that tomato and sugar are primary ingredients in ketchup, you’d have school cafeterias all over the nation scrambling to get such a hazardous condiment out of the premises if that combo was really as dangerous as your trollish friend suggests.
Forget soda pop… the real danger to today’s schoolchildren is ketchup, which will eat its way through an automobile paint job (and possibly their tender little stomach linings). WON’T SOMEONE THINK OF THE CHILDREN???
I’ve never seen it, but the acid in ketchup will supposedly eat through paint. I can understand that, as it happens often with bird shit, but that would only happen directly under the ketchup/birdshit. I don’t know how sugar could be related, and don’t believe the paint will come off in sheets.
Sometimes, once a car loses a little paint, more paint will slowly come off and make the bare spot larger, or if you blew high pressure air or water at the edge of the paint, it can take the paint off in fairly small pieces. Nothing I would call “sheets” though, but maybe that’s what he saw.
Tomatoes are quite acidic, and acid will dissolve metals. It’s not uncommon to find hidden way back in a cupboard a can of tomatoes or tomato sauce that has eaten through the can enough for the contents to leak out and make a sticky mess all over the cupboard shelf. Tomatoes don’t peel the skin off your lips and mouth because that isn’t metal, and because you don’t leave it in your mouth for any amount of time.
The real response to this is “yeah, so what?”. Did they think this was something extraordinary?
Lemon juice is even more acidic, but I use it on fish I eat, and I drink lemonade. Even water will rust through thick iron girders and make bridges or buildings fall down, but I drink several glasses of the stuff every day. And I season my food with a combination of a metal that bursts into flame and a poisonous gas (sodium chloride, i.e. salt). So what? Ask that person just what his point is.
Yeah but to reach the metal they’ll have to penetrate the clear and base coat(s), correct? Assuming their aren’t any bare spots, as previously mentioned.
Given enough time I suppose it may be possible. I’ve never seen tomatoes eat through cans, but I suppose it might happen. Tomatoes have a pH of about 4-4.5, which is acidic, but less acidic than foods like peaches, plums, and even strawberries. Lemons (which you mention) and limes are in the 2.0 range. I’m fairly confident I could leave a lemon on my car for several days or weeks and not have sheets of paint peeling off my car. Now what sugar has anything to do with the corrosion is anyone’s guess.
Hell, I’d be willing to risk my cars paint job to prove the point that tomato and sugar ain’t going to peel the paint off your car in sheets.
I still don’t believe the “in sheets” part, but bird poop will eat through the paint and, according to the internet, it has a pH between 3.5 and 4.5. If tomatoes are 4 to 4.5, I’m inclined to believe they would affect the paint similarly.
I think the answer to the “why sugar” question is ketchup. A lot of contemporary internet-spread folk beliefs work exactly this way: take something that is technically true, describe it in terms that combine the ordinary and the apocalyptic, and all of a sudden “ketchup is quite acidic” becomes “tomato and sugar will peel the paint from your car in strips!”
And I’d believe that ketchup, in a large enough amount and with some time would damage the paint on a car.
Ketchup is acidic (corrosive?) enough to clean the green stuff off of old pennies & make them look brand new again - a fun, if fairly useless piece of knowledge my grandfather taught me. And vinegar, a main ingredient in ketchup, will eat through an eggshell in a couple of days - raw eggs enclosed only in the membrane with no shell are really cool, btw.
That’s because the acid reacts with the copper oxide. The acetic acid reacts with the copper oxide, but not with the copper or zinc, IIRC, in this cleaning process. (And, in my experience, they don’t look brand new again. They’re clean, but dull.) That doesn’t necessarily mean ketchup will corrode most everything else.
That said, I wouldn’t be surprised that given enough time and the right circumstances, ketchup can damage a car’s paint job. I know they say bird poop can damage your car’s paint job, but I’ve had bird shit caked on my car for weeks when I was on vacation to no apparent ill effect. So I’m assuming it must take a long time or involve certain paints or defects in the finish.