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Jody was working near the acid vats one day when she noticed some aluminum on the floor that was quite corroded from some of the acid that had spilled on it. She then made his way to the top of the vat to inspect some equipment. There was a tour and the group just happened to be coming by the vats just then. The guide pointed to the warning signs on the vats that read "caution: corrosive" and went to move on, but as luck would have it Jody recognized someone in the group and leaning over the railing to wave, slipped and plunged into the vat.

The crowd gasped sure that the Jody would be instantly dissolved by the acid. Another worker rushed over and pulled her out. Jody yelled down "I'm ok".

The guide remarked that wasn't part of the tour and asked people to move on.

If Jody wasn't wearing any protective clothing or had any special protection form the acid, how did she survive.

I expect this to be solved almost immediately, guys.

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Hey what about my coke cola. It contains phosphoric acid. And i drink it everyday. It shld work. Furthermore its used as an oxide remover. The oxide layer that is protecting the AL shld corroded away by phosphoric acid.

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Hey what about my coke cola. It contains phosphoric acid. And i drink it everyday. It shld work. Furthermore its used as an oxide remover. The oxide layer that is protecting the AL shld corroded away by phosphoric acid.

i Guess so... but does it completely corrode the aluminum?

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the aluminum was corroded over a relatively long time span, and the acid was of relatively low concentration, perhaps NaOH, that it did not seriously harm Jody. The puzzle's trick is that most people will imagine the aluminum was corroded recently because Jody has just noticed it.

edit: i just noticed the accepted answer just now!

Edited by walczyk
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Jody was working near the acid vats one day when she noticed some aluminum on the floor that was quite corroded from some of the acid that had spilled on it. She then made his way to the top of the vat to inspect some equipment. There was a tour and the group just happened to be coming by the vats just then. The guide pointed to the warning signs on the vats that read "caution: corrosive" and went to move on, but as luck would have it Jody recognized someone in the group and leaning over the railing to wave, slipped and plunged into the vat.

The crowd gasped sure that the Jody would be instantly dissolved by the acid. Another worker rushed over and pulled her out. Jody yelled down "I'm ok".

The guide remarked that wasn't part of the tour and asked people to move on.

If Jody wasn't wearing any protective clothing or had any special protection form the acid, how did she survive.

I expect this to be solved almost immediately, guys.

may be the vat was covered, she actually didn"t fell in acid...

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Acetic acid is mildly corrosive to metals including iron, magnesium, and zinc, forming hydrogen gas and salts called

acetates. Aluminium, when exposed to oxygen, forms a thin layer of aluminium oxide on its surface, which is relatively

resistant to the acid, allowing aluminium tanks to transport acetic acid. (from wiki) Acetic acid is the acid in vinegar

Aluminum is actually a very active metal, meaning that its

nature is to oxidize very quickly. While a weakness for most

metals, this quality is actually the key to its ability to resist

corrosion. When oxygen is present (in the air, soil, or water),

aluminum instantly reacts to form aluminum oxide. This

aluminum oxide layer is chemically bound to the surface, and

it seals the core aluminum from any further reaction. This

is quite different from oxidation (corrosion) in steel, where

rust puffs up and flakes off, constantly exposing new metal

to corrosion. Aluminum’s oxide film is tenacious, hard, and

instantly self-renewing.

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Acetic acid is mildly corrosive to metals including iron, magnesium, and zinc, forming hydrogen gas and salts called

acetates. Aluminium, when exposed to oxygen, forms a thin layer of aluminium oxide on its surface, which is relatively

resistant to the acid, allowing aluminium tanks to transport acetic acid. (from wiki) Acetic acid is the acid in vinegar

Aluminum is actually a very active metal, meaning that its

nature is to oxidize very quickly. While a weakness for most

metals, this quality is actually the key to its ability to resist

corrosion. When oxygen is present (in the air, soil, or water),

aluminum instantly reacts to form aluminum oxide. This

aluminum oxide layer is chemically bound to the surface, and

it seals the core aluminum from any further reaction. This

is quite different from oxidation (corrosion) in steel, where

rust puffs up and flakes off, constantly exposing new metal

to corrosion. Aluminum’s oxide film is tenacious, hard, and

instantly self-renewing.

Good post, swongy, and welcome to the den. Please use spoilers in the future. I also noticed a weakness in this puzzle after the correct answer was posted. If this was a pickling factory, the visitors must have known that and wouldn't expect the vinegar to "instantly dissolve" Jodi.

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Vinegar cant dissolve aluminum, not at an observable rate. Especially not that kind of weak acid we have in food grade acetic acid.

H3PO4 can't dissolve aluminum either. (stuff found in coke) Unless you are talk about mass action effect. Whereby the rate of the reaction is proportional to the concentration of the reactants.

We would require some heavy duty acids like conc HCL or conc NaOH. However coke cola factorys, the H3PO4 they are using for that citrus flavour, before added to coke, its highly concentrated. Enough for the trucks transporting them to carry a hazardous material sign onboard. The concentrated form is irritating to skin and mucous membranes. (possibly Jodi gt thick skin)

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