Household Chemistry
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10-11-2012, 07:33 PM
Household Chemistry
I'd just like to post some simple chemistry reactions that are neat or useful that can be performed safely with common household chemicals.


The first one is useful for when you have dishes with nasty lime deposits. Lime is calcium carbonate, CaCO3, and is naturally found dissolved in water. When water containing calcium carbonate evaporates, the CaCO3 is left behind as faint white spots on your dishes, especially visible on glassware.

CaCO3 can be a pain in the butt to get off of your dishes. Normal soap does not attack it, or does so only weakly. It's time for some chemistry.

CaCO3 will react with acetic acid (aka vinegar) to create calcium acetate and carbon dioxide. The calcium acetate dissolves off the glass and into the water, so it can be poured down the drain, leaving your glassware clean. Great! But there's a problem: this process is very slow, taking at least a couple hours to completely remove the lime stains.

That's where our second reagent comes in: isopropyl alcohol, or "rubbing alcohol". Isopropyl is only a very weak acid, and interacts mainly through Van der Waals forces (the forces that allow chameleons to cling to walls and ceilings). It won't do anything to CaCO3 on its own. But mix it with acetic acid, and it will work as a catalyst to speed the reaction up enormously.


So simply take your glass, fill it with one (1) part distilled white vinegar, one (1) part 70% or 91% rubbing alcohol, and two (2) parts hot water. You'll immediately see bubbles form and rise to the top of the glass; this is the carbon dioxide released as the calcium in CaCO3 bonds with the acetic acid. Within 5 to 15 minutes your glass should be spot-free.

This mixture is also a good general purpose glass and tile cleaner, when you need something with a bit more "oomph" than Windex.



WARNING: Isopropyl alcohol is toxic to ingest, and does release fumes. Use in a ventilated area. If you start to get a headache, go outside immediately to clear your head.

E 2 = (mc 2)2 + (pc )2
614C → 714N + e + ̅νe
2 K(s) + 2 H2O(l) → 2 KOH(aq) + H2 (g) + 196 kJ/mol
It works, bitches.
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10-11-2012, 07:50 PM
RE: Household Chemistry
I'd like to bring this one up, not as something you can do, but as something you SHOULD NOT DO under any circumstances.

Do not mix bleach with ANYTHING. I mean, there are some things you can mix it with, but the vast majority of chemicals in the home, when mixed with bleach, will cause Bad Things to happen. Bad things being explosions, toxic fumes like chlorine gas, ridiculously caustic mixtures that eat through plastic, and fires. Just... leave bleach on its own. It's a powerful cleaning agent because of its oxidizing properties, but while those oxidation reactions are great for busting grime, they also tend to be pretty violent when they occur with simpler chemicals.


Respect the power of bleach. Don't play with it.

E 2 = (mc 2)2 + (pc )2
614C → 714N + e + ̅νe
2 K(s) + 2 H2O(l) → 2 KOH(aq) + H2 (g) + 196 kJ/mol
It works, bitches.
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10-11-2012, 07:56 PM
RE: Household Chemistry
So... Why is it that bleach is so volatile?

And what would happen if it were poured down a cars gas intake?

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10-11-2012, 08:09 PM
RE: Household Chemistry
(10-11-2012 07:33 PM)Phaedrus Wrote:  I'd just like to post some simple chemistry reactions that are neat or useful that can be performed safely with common household chemicals.


The first one is useful for when you have dishes with nasty lime deposits. Lime is calcium carbonate, CaCO3, and is naturally found dissolved in water. When water containing calcium carbonate evaporates, the CaCO3 is left behind as faint white spots on your dishes, especially visible on glassware.

CaCO3 can be a pain in the butt to get off of your dishes. Normal soap does not attack it, or does so only weakly. It's time for some chemistry.

CaCO3 will react with acetic acid (aka vinegar) to create calcium acetate and carbon dioxide. The calcium acetate dissolves off the glass and into the water, so it can be poured down the drain, leaving your glassware clean. Great! But there's a problem: this process is very slow, taking at least a couple hours to completely remove the lime stains.

That's where our second reagent comes in: isopropyl alcohol, or "rubbing alcohol". Isopropyl is only a very weak acid, and interacts mainly through Van der Waals forces (the forces that allow chameleons to cling to walls and ceilings). It won't do anything to CaCO3 on its own. But mix it with acetic acid, and it will work as a catalyst to speed the reaction up enormously.


So simply take your glass, fill it with one (1) part distilled white vinegar, one (1) part 70% or 91% rubbing alcohol, and two (2) parts hot water. You'll immediately see bubbles form and rise to the top of the glass; this is the carbon dioxide released as the calcium in CaCO3 bonds with the acetic acid. Within 5 to 15 minutes your glass should be spot-free.

This mixture is also a good general purpose glass and tile cleaner, when you need something with a bit more "oomph" than Windex.



WARNING: Isopropyl alcohol is toxic to ingest, and does release fumes. Use in a ventilated area. If you start to get a headache, go outside immediately to clear your head.
Just something that has been bugging me while reading your post. How does alcohol act as a catalyst in this reaction? I was thinking that the fact that you used hot water could have sped up the reaction many times due to kinetic reasons. The only reaction between acids and alcohols I can think of offhand is esterification, where the acid and alcohol molecules join together under certain conditions to form an ester.

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10-11-2012, 08:10 PM (This post was last modified: 10-11-2012 08:17 PM by Phaedrus.)
RE: Household Chemistry
Bleach is volatile because it is based on chlorine, which is a very potent oxidizer. That means that it wants to take electrons from other atoms and keep them to itself. Oxygen, naturally, was one of the first oxidizers discovered and is a very potent one. Most of the oxygen in the air is already bonded with other atoms, so it is no longer (as) reactive.

Chlorine is an even stronger oxidizer than oxygen. It really, really wants to steal electrons from other atoms, and will do so with great violence. It will even tear oxygen away from a molecule (often tearing the whole molecule apart) and bond in its place, releasing oxygen... which then oxidizes with whatever it can get its hands on. And every single time one of these reactions takes place, heat is generated. If it takes place very quickly it causes an explosion. Otherwise it can cause a fire.

Bleach will also, if mixed with an acid, decompose into plain chlorine gas (Cl2). Chlorine gas is famous for its use as a chemical weapon during the first World War, attacking the eyes and lungs of its victims. It is also a strong oxidizer and will violently react with other chemicals in the environment if the concentration is great enough.



Rocket fuels use a mixture of a fuel component (like liquid Hydrogen or Kerosine) and an oxidizer (like liquid Oxygen or Ammonium Perchlorate). The oxidation reaction creates so much heat and expansion of gas that it verges on an explosion, and the directed expansion of gas is what propels the rocket. The same principle also lies behind gunpowder. The difference between these reactions and bleach's reactions is that rocket fuel or gunpowder needs a spark to ignite; chlorine will start reacting at room temperature.


Of course, chlorine isn't nearly as reactive as its little brother, fluorine. But you won't find F2 or elemental Fluorine outside of a professional chemistry lab or chemical plant, so don't worry about it.

E 2 = (mc 2)2 + (pc )2
614C → 714N + e + ̅νe
2 K(s) + 2 H2O(l) → 2 KOH(aq) + H2 (g) + 196 kJ/mol
It works, bitches.
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10-11-2012, 08:14 PM (This post was last modified: 10-11-2012 08:20 PM by Phaedrus.)
RE: Household Chemistry
(10-11-2012 08:09 PM)robotworld Wrote:  Just something that has been bugging me while reading your post. How does alcohol act as a catalyst in this reaction? I was thinking that the fact that you used hot water could have sped up the reaction many times due to kinetic reasons. The only reaction between acids and alcohols I can think of offhand is esterification, where the acid and alcohol molecules join together under certain conditions to form an ester.

I tried it with hot water too; that speeds it up somewhat, but not nearly as much as the alcohol. I discovered the acetic acid + isopropyl reaction originally using both chemicals at room temperature. The hot water just makes it go even faster. I believe the isopropyl has molecular interactions with the CaCO3 that lift it off the surface of the glass and into weak solution. Normally the CaCO3 would immediately deposit again, but in this case the acetic acid is available to react with it and create calcium acetate.

Isopropyl alcohol is an effective solvent, but not because of its extremely mild acidity; it is a good solvent because it interacts with all sorts of organic molecules through various forces like Van der Waals and hydrogen bonds, etc. I think it's acting on the carbonate group, in this case.



Isopropyl and acetic acid will not esterify without sulfuric acid to catalyze the reaction.

E 2 = (mc 2)2 + (pc )2
614C → 714N + e + ̅νe
2 K(s) + 2 H2O(l) → 2 KOH(aq) + H2 (g) + 196 kJ/mol
It works, bitches.
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10-11-2012, 08:17 PM
RE: Household Chemistry
(10-11-2012 07:56 PM)Free Thought Wrote:  So... Why is it that bleach is so volatile?

And what would happen if it were poured down a cars gas intake?
I heard that there are various types of bleach. The chlorine based bleaches are the more noxious ones.
Chlorine based bleaches if I'm not mistaken contain NaClO (sodium hypochlorite), which is a bleaching agent. Most reactions with NaClO give out toxic chemicals. For example:

NaClO + hydrochloric acid gives out chlorine
NaClO + nitrogenous compounds (such as ammonia) gives out very volatile gases (NH2Cl, NHCl2, NCl3)

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10-11-2012, 08:18 PM
RE: Household Chemistry
I think I will have too keep an eye on this thread, learn some chemistry stuff for a change. Lord knows I need to actually learn something new, science wise.

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10-11-2012, 08:38 PM
RE: Household Chemistry
(10-11-2012 08:14 PM)Phaedrus Wrote:  
(10-11-2012 08:09 PM)robotworld Wrote:  Just something that has been bugging me while reading your post. How does alcohol act as a catalyst in this reaction? I was thinking that the fact that you used hot water could have sped up the reaction many times due to kinetic reasons. The only reaction between acids and alcohols I can think of offhand is esterification, where the acid and alcohol molecules join together under certain conditions to form an ester.

I tried it with hot water too; that speeds it up somewhat, but not nearly as much as the alcohol. I discovered the acetic acid + isopropyl reaction originally using both chemicals at room temperature. The hot water just makes it go even faster. I believe the isopropyl has molecular interactions with the CaCO3 that lift it off the surface of the glass and into weak solution. Normally the CaCO3 would immediately deposit again, but in this case the acetic acid is available to react with it and create calcium acetate.

Isopropyl alcohol is an effective solvent, but not because of its extremely mild acidity; it is a good solvent because it interacts with all sorts of organic molecules through various forces like Van der Waals and hydrogen bonds, etc. I think it's acting on the carbonate group, in this case.



Isopropyl and acetic acid will not esterify without sulfuric acid to catalyze the reaction.
I agree with what you said regarding how alcohol is able to first "lift" the CaCO3 sediments off the glass (probably because the interactions between alcohol are more favourable than the interactions between glass), thus increasing the surface area available for reaction. This is when ethanoic acid comes in, reacting with CaCO3, but at a higher rate due to increase surface area for reaction. Am I right to say that? Smile

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10-11-2012, 08:42 PM
Household Chemistry
How would one make a quick killing poison out of household items that can't be traced by forensics?

Oh, and while you're at it, how would one build a car bomb out of household items?

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