permaculture

[Lawrence London <lfljvenaura@gmail.com>]

[I highly recommend Reddit for info and Q&A on many topics, populated by
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FYI: labels = general environmental, travel to outback, potable water, food
safety, long but useful thread | Fwd: Why is Chlorine so effective in
killing anything alive? : askscience
Subject: Why is Chlorine so effective in killing anything alive? :
askscience
http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/
Biology: Why is Chlorine so effective in killing anything
alive?<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/>
self.askscience <http://www.reddit.com/r/askscience/>

submitted 9 hours ago by chr0no <http://www.reddit.com/user/chr0no>

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
BioChemistryStudent <http://www.reddit.com/user/BioChemistryStudent> 1
point2 hours ago

Another point I would raise from a biochemical point of view, is that Cl-
in solution is used by most organisms to help maintain osmotic gradients,
and prevent themselves from taking too much water and dieing. It's a bit
more complicated than that, but adding a 'large' volume of Cl- ions to any
living organism's habitat is going to alter the equilibrium it's existing
it, and will either desiccate it, or cause it to swell so much it pops. Cl-
is also used in alot of secondary transport systems, and can gum up those
works as well.

In P.Chem the other day we were talking about how the concentration of ions
in solutions changes the interactions between phospholipids, and I would
hypothesis that the Cl- ions are also weakening the polar-polar head-group
interactions between the phospholipids.

So, to recap; the ions in solution will change the osmotic pressure of the
cell, as well as weaken the cell membrane, allowing them to be lysed, thus
killing your microbes.

There are exceptions to this however, the Halophile family of bacteria can
live in extremely high concentrations of salt. Staph. Aureus for example,
is normally a helpful bacteria that lives on your skin, it can survive in
up to 12% NaCl solution. Chlorine doesn't kill everything, but it does a
good job with those not used to it.

Hope that help!

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Throwaway1944719115 <http://www.reddit.com/user/Throwaway1944719115> 1
point2 hours ago

Just FYI, diluted Chlorine bleach disinfects better than concentrated
bleach. Also it works best when left on surfaces for 15 minutes, does
almost nothing if sprayed on and wiped off immediately.

To answer the question. Chlorine destroys the cell membrane and destroys
the DNA inside, the component that allows for cellular reproduction.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
lyricandverse <http://www.reddit.com/user/lyricandverse> 3 points 3 hours
ago

Also - from a physiological standpoint - it's important to note that when
chlorine gets into the lungs and HASN'T reacted with body tissue, the free
molecules will react with water turning it into hydrochloric acid gas.
So...what doesn't alter your actual body-chemistry, corrodes it.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
12and32 <http://www.reddit.com/user/12and32> 3 points 4 hours ago

When chlorine steals electrons from whatever it can, the atoms that it
steals electrons from undergo shifts in their bonds and their geometry.
This causes molecules bound to these atoms to undergo conformational
shifts, or changes in their superstructure. Most biomolecules only operate
in their intended 3D form; disrupt this, and their structure can change,
lose parts, or even collapse.

What complicates this is the reaction that chlorine undergoes when it
contacts water.

Cl2 + H2O -> HClO + HCl

Hypochloric acid, the first product, is not only an acid (albeit weak), but
its conjugate base, the hypchlorite ion, is a strong oxidizer. Hydrochloric
acid is a very strong acid. Acids also induce conformational changes,
though through a different mechanism.

Highly-electronegative atoms like oxygen can act as proton acceptors via
extra electron pairs. This also induces conformational changes; the oxygen
molecule becomes less negative, which can affect the entire molecule
through shifts in where bonds are located, since the oxygen attempts to
shed that proton to return to a standard two unpaired pairs of electrons.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
jcpuf <http://www.reddit.com/user/jcpuf> 0 points 4 hours ago

Physiologists: I've wondered for some time whether the chlorine gas, upon
reducing to the chloride anion, would make the mucous lining of the lungs
more hypertonic, and in so doing draw more fluid across the alveolar walls
into the lungs. Persistent cough is a symptom of chlorine gas exposure, but
I'm not sure that that isn't just somehow a response to the reduced oxygen
gas.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
base736 <http://www.reddit.com/user/base736> 1 point 5 hours ago

Follow-up question... It seems like chlorine occurs in a lot of pesticides
(many of these <http://www.pops.int/documents/pops/>, for example). Is this
coincidence, does chlorine act similarly when bonded to an organic molecule
as it does when it's in its elemental form, or is something else at work
here? [http://www.pops.int/documents/pops/]

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
pound-sign <http://www.reddit.com/user/pound-sign> 25 points 6 hours ago*

To add to /u/TimeToHaveSomeFun <http://www.reddit.com/u/TimeToHaveSomeFun>'s
comment, in the context of water disinfection, the mechanism by which
Chlorine kills pathogens in water varies: it is thought to either directly
oxidize genetic material or destroy cell membranes.

Chemically, chlorine gas (bleach and calcium hypochlorite are also common
species for disinfection) reacts in water to form an equilibrium with
hypochlorite and hydrochloric acid. The hypochlorite is important because
it then forms an equilibrium with the highly effective oxidizing agent
hypochlorous acid. I hope that was ELI5...sorry.

It is also interesting to note that chlorination is NOT effective against
hard-shelled cysts (e.g Giardia, which you may have hear of). This is one
reason why affluent areas are turning away from chlorine water treatment
plants (or, most often, using chlorine in conjunction with another
disinfectant), though you still get the most "bang for you buck" with
chlorine.

(Note: the other disadvantage you may have heard about chlorine is in
regards to disinfection by products, also it's sensitivity to organic
matter... if you're interested in these or other water disinfectants, let
me know. I can also point you to some sources if you're interested).

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
2babou <http://www.reddit.com/user/2babou> 3 points 1 hour ago

ok, this really interests me and I'd like to discuss it some. I'm a Peace
Corps Volunteer in West Africa right now and quite familiar with giardia. I
had no idea bleach wasn't effective against it! I've been doing
sensitivizations with villagers talking up chlorine and how it'll pretty
much eliminate their water borne diarrhea...was I lying??? :O what kills
giardia then? One comment lower down mentioned UV disinfection? That's
tough here, all the plastics are chalk full of bpa I'm guessing.

Please elaborate on the chlorine byproducts (which I know a little on) and
sensitivity to organic matter (which really interests me). Do you mean that
organic matter tends to "use up" a lot of chlorine, rendering it inactive
and inefficient in water that hasn't been strained of it?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
just_an_ordinary_guy <http://www.reddit.com/user/just_an_ordinary_guy> 1
point 5 minutes ago

Water treatment operator here. The way we reduce our disinfection by
products is by not using chlorine on the dirty side. We can do this because
of a certain process we use that doesn't store mud for months or years in
the sedimentation process.

Organic matter does use up chlorine. That's why we use chlorine. There have
been long term studies that disinfection byproducts probably cause a slight
increase in cancer, but when you have serious water borne illnesses as the
alternative, I'll take the former.

We have big filters that use GAC. If you run water through a filter and
then chlorinate it, you're probably going to be alright. You should never
rely on just one method anyway. If it is dirty water, run it through a sand
filter first.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Gbcue <http://www.reddit.com/user/Gbcue> 1 point 56 minutes ago

Filtration is great against *Giardia*. RO/nano/ultrafiltration are the
best. Chlorine will inactivate *Giardia*, provided it has enough contact
time (CT). Without enough CT, chlorine won't kill anything, though. UV does
kill *Giardia*, but I prefer using a physical filter.

Yes, the more organic matter (bacteria, dead animals, organics) uses up
more of the available chlorine. Chlorine actively oxidizes the matter and
attaches to make other salts, you know, chemistry, so that the chlorine
ions are not available anymore.

Source: I'm a drinking water engineer.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
noguchisquared <http://www.reddit.com/user/noguchisquared> 2 points 56
minutes ago

A couple clicks got me to the CDC backcountry water treatment site:
http://www.cdc.gov/healthywater/drinking/travel/backcountry_water_treatment.html

That might be useful, and it talks about giardia.

I wouldn't fret about chlorine by-products. It's a long-term health
concern, where having sanitary water is a short-term concern. Basically,
the chlorine is very reactive and will form chlorinated organic compounds.
The treatment plant I visited over the summer (medium city) using alum
flocculation mostly to decrease the amount of dissolved organics in the
water. When I say dissolved, it is only the portion that can pass through a
micrometer pore size filter, and so it can't be simply screened.

Fun facts: The plant I visited spends about $1 million annually on this
problem, removing dissolved organics. The person who discovered DBPs was
working in a brewery.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
huellbordineaux <http://www.reddit.com/user/huellbordineaux> 2 points 3
hours ago

To add a bit to this, I work professionally in swimming pools, and many
commercial pools are adding ultra-violet light systems (in addition to EPA
recommended chlorine levels) specifically to help in the fight against
Giardia

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Gbcue <http://www.reddit.com/user/Gbcue> 2 points 1 hour ago

UV can only do so much without a multi-barrier treatment method such as
filtration.

Source: I'm a drinking water engineer.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
JaxHostage <http://www.reddit.com/user/JaxHostage> 12 points 6 hours ago

Chlorine chemically reacts with the moisture in your lungs, nose, throat,
eyes, and on your skin, and creates hydrochloric acid. The acid burns the
various tissues in your body, your body reacts by attempting to flush the
containment out, which provides more moisture for the chlorine to react
with, creating more hydrochloric acid. In burning the lining of the lungs
your body is no longer able to extract oxygen from the air, coupled with
your lungs rapidly filling with fluid, you suffocate. All of this depends
on the concentration and duration of exposure, IF you survive chemical
burns are an certainty.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
TimeToHaveSomeFun <http://www.reddit.com/user/TimeToHaveSomeFun> 391
points6 hours ago

Chlorine is a very effective oxidizing agent, meaning it is capable of
oxidizing a lot of things while itself getting reduced in the process.
Intuitively, this makes sense because the chlorine atom is very
electronegative (meaning that it's happier existing as reduced Cl- anions
as opposed to neutral Cl in Cl2). Chlorine also has a very positive
standard reduction potential, meaning that it is capable of reducing
anything with a lower potential, which just so happens to be most things.
Because of this, chlorine can attack a huge variety of molecules, including
most carbon-based compounds. Thus, it can effectively destroy living things.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
karanj <http://www.reddit.com/user/karanj> 1 point 44 minutes ago

ELI5 version: it steals electrons because it's more negative, making bonds
between the atoms in the molecule weak or broken.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Insert_Release <http://www.reddit.com/user/Insert_Release> 1 point 2 hours
ago

Is chlorine more oxidizing than h2o2?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
DFTricks <http://www.reddit.com/user/DFTricks> 1 point 3 hours ago

What happens if you mix Cl with fluoride acid before using it on an organic
material?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
nolan1971 <http://www.reddit.com/user/nolan1971> 1 point 35 minutes ago

Nothing. Fluoride is more reactive than Chlorine, so there's not going to
be any reaction (under normal conditions). See:
http://www.avon-chemistry.com/chem_intro_lecture.html, more specifically:
http://www.avon-chemistry.com/ch9_chart11.jpg

Incidentally, Chlorine is an element that likes to form homonuclear
molecules <http://en.wikipedia.org/wiki/Homonuclear>, so it'd be more
correct to ask "What happens if you mix Cl2 with fluoride acid...".

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Asddsa76 <http://www.reddit.com/user/Asddsa76> 8 points 3 hours ago

Chlorine is a very effective oxidizing agent

Somewhat unrelated, but does this mean fires can use chlorine gas instead
of oxygen to burn?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
TimeToHaveSomeFun <http://www.reddit.com/user/TimeToHaveSomeFun> 5 points 1
hour ago

Yes. Fires are simply oxidation of carbon materials via oxygen. You can
also oxidize carbon materials via chlorine, and there will be similar,
highly exothermic reactions. Unfortunately, the word "oxidation" is a bit
confusing because it implies that oxygen has to be around.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
erikdhoward <http://www.reddit.com/user/erikdhoward> 1 point 5 hours ago

Follow-up:
Cl2 + H2O → HOCl + HCl
>From this point, does the H+ do most of the damage by means of organic
reactions with surrounding cellular membranes? If so, what is the
predominant reaction taking place (took both organics quite a while ago).
If not, what is happening?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
pound-sign <http://www.reddit.com/user/pound-sign> 1 point 4 hours ago

Nope; I'll repeat what I said below here. Hypochlorous acid* is the most
important oxidizing agent for water disinfection. Here's the ideal
reaction: (sorry about the formatting)
Cl2+ H2O <--> HOCl +HCl
*HOCl<-->H+ + OCl-
HCl <-->H+ + Cl-

The second reaction is commonly referred to as the "free chlorine
residual", a term you may have come across. A 1:1 ratio of chlorine gas to
free chlorine residual is produced in an ideal system...but the reaction is
greatly hindered by the presence of organic matter. Let me know if you want
me to point you to some reading.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
theappstyle <http://www.reddit.com/user/theappstyle> 5 points 5 hours ago*

This is a tab bit incomplete. The terms bleaching and chlorinating actually
refers to the activity of three active compounds - hypochlorite (ClO-),
what you find in commercial bleach, Cl- (the chlorine anion, which can come
from many things, including table salt), and Cl2 (the diatomic chlorine
gas). They are all oxidative species, meaning they tend to break up *double
bonds* (ubiquitous in biological molecules) and insert themselves and other
atoms in. The resulting changes usually destroys the function of the target
molecule, especially if the target is DNA, because it messes up their shape
and their intermolecular interactions (how they 'communicate' with other
biological molecules).

Hypochlorite is particularly effective because its oxidative potential is
so high. That means any biological molecule it comes into contact with is
going to be unable to resist the kind of chemistry it wants to do (which is
to mess up the target molecule).

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
rightsideofthelane <http://www.reddit.com/user/rightsideofthelane> 1
point1 hour ago

Hyopchlorite has actually been shown to be the main antibacterial component
of bleach as well. It has been shown to break apart peptidoglycan.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
pfftYeahRight <http://www.reddit.com/user/pfftYeahRight> 6 points 5 hours
ago

Sorry, but what is oxidizing? It's been a few years since I last took a
chem class.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Almustafa <http://www.reddit.com/user/Almustafa> 1 point 15 minutes ago

Oxidation is the 'loss' of electrons, usually by forming a bond to a highly
electronegative element, like Fluorine, Chlorine, or Oxygen.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
geefzilla <http://www.reddit.com/user/geefzilla> 3 points 2 hours ago

There's a couple useful mnemonics that a lot of people I know use to help
the whole oxidation/reduction thing stick. OIL RIG (Oxidation is loss,
reduction is gain) or LEO GER (Lose electrons oxidation, gain electrons
reduction. Think of it like a growling lion I guess.)

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
neilk <http://www.reddit.com/user/neilk> 6 points 4 hours ago*

Here are some examples of oxidation: when iron turns into rust, or when
wood burns into ash.

Chemists called it oxidation because the first known examples were all
about combining with oxygen. When iron combines with oxygen, you get rust.
And a wood-burning fire is a reaction, started by heat and then releasing
more heat, where carbon molecules combine with oxygen.

However, chemists eventually decided that oxidation was really a more
general concept than just oxygen. Confusingly, they continue to call it
"oxidation", even if there is no oxygen involved. Anyway, they use a number
called "oxidation state" to describe the kinds of reactions that a molecule
"wants" to have, or the kinds of bonds it could form with other molecules.
This is useful when predicting the reaction that occurs when combining two
molecules.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
trademark148 <http://www.reddit.com/user/trademark148> 8 points 4 hours ago

Oxidizing is the opposite of reduction, which is gain electrons. I find it
easier to remember this way because when something gains electrons, it's
charge goes down, or is reduced. Also, an oxidizing agent cause
oxidization, so it undergoes reduction and vice versa

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
295f423c5f2b37416d6a <http://www.reddit.com/user/295f423c5f2b37416d6a> 1
point 5 hours ago

Nearly everything else. In general, any substance that can undergo
decomposition via oxidation of the weakest (electronegatively) constituent
chemical bond. In most conditions, this means chlorine is looking to turn
something (anything) into some kind of chloride. This kind of electrophilic
addition <https://en.wikipedia.org/wiki/Electrophilic_addition> is enough
to wreak havoc on most biological molecules.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
jeffiguritout <http://www.reddit.com/user/jeffiguritout> 1 point 6 hours ago

Why isn't fluorine used instead? IIRL it is better than Cl- in all those
aspects and forms the stronger acid HF

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
ChainBlue <http://www.reddit.com/user/ChainBlue> 3 points 3 hours ago

The explain-it-like-I-am-5 answer is that it is too good at being a nasty
chemical vs chlorine. Too reactive, harder to container, harder to clean
up, nastier tissue damage if you are exposed, etc....

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
295f423c5f2b37416d6a <http://www.reddit.com/user/295f423c5f2b37416d6a> 1
point 4 hours ago

The difficulties inherent to storing and/or transporting fluorine are
prohibitively high. Unless you've got airtight teflon containers and
environment suits, you shouldn't be screwing with F2.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
theappstyle <http://www.reddit.com/user/theappstyle> 6 points 5 hours ago

Fluoride (F-), while being the most electronegative (electron-grabby) ion
on the period table, is not particularly nucleophilic (able to donate its
own electrons and form a bond). Therefore, even though it really wants to
share electrons with other molecules, it's pretty bad at securing the deal.

Consequently, it doesn't do a lot of chemistry on biological molecules.

Now, hydrofluoric acid (HF) is actually *much weaker* than (HCl), and their
relative acidities is *not* directly related to the question at hand.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
vondur <http://www.reddit.com/user/vondur> 6 points 5 hours ago

Fluorine is extremely reactive, even more so than Chlorine, it's not safe
to work with. HF is so reactive that you can't store it in glass. It's the
substance that is used to dissolve Si02 and make silicone wafers for
microprocessors. HF technically is not a strong acid, but is very corrosive
and poisonous.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
waffles4theworld <http://www.reddit.com/user/waffles4theworld> 5 points 5
hours ago

By chemical definitions, HF is a weak acid. In contrast, HCl is a strong
acid.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Almustafa <http://www.reddit.com/user/Almustafa> 1 point 9 minutes ago

While that is true, HF is way, way nastier than HCl. The whole weak/strong
acid thing just means that HF is more often not dissociated in water than
it is dissociated (it floats around as HF not H+ F- in solution). Depending
on the concentration, HCl will cause tissue damage and chemical burns. If
you get HF on your skin in any concentration, it's ER time.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Funkit <http://www.reddit.com/user/Funkit>Aerospace Design | Manufacturing
Engineer. 13 points 5 hours ago

HF is very toxic. HCL would cause chemical burns but HF disrupts processes
in Bone Marrow and can poison with very little contact, even after washed
off.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Truck43 <http://www.reddit.com/user/Truck43> 14 points 6 hours ago

It can also be itself oxidized, but ClF3 is something you only want to read
about.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Xavs42 <http://www.reddit.com/user/Xavs42> 218 points 6 hours ago*

On a slightly larger (human body) level, it's heavier than air, so when
inhaled, it gets very hard to get out of the lungs once it's in there. It
starts to just react with all the cells around it, forming hydrochloric
acid, and hypochlorous acid. Which are pretty terrible things to have in
your lungs.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
chr0no 
<http://www.reddit.com/user/chr0no>[S<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/>
] 2 points 2 hours ago

Isn't that the same acid that we have in our stomachs?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
singularityJoe <http://www.reddit.com/user/singularityJoe> 1 point 2 hours
ago

Yes

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
WarriorHealer <http://www.reddit.com/user/WarriorHealer> 1 point 3 hours ago

Well said. Neutrophil's make HOCl to destroy pathogens, especially in the
lungs, albeit in very small amounts.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
FLAGSHIP <http://www.reddit.com/user/FLAGSHIP> 4 points 5 hours ago

Is this the effect that causes pain and redness in your eyes after having
them open for extended periods of time in a chlorinated pool?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
dukhsan <http://www.reddit.com/user/dukhsan> 9 points 5 hours ago

Chlorine *disproportionates* in water - hydrochloric acid sees the Cl atom
reach oxidation state -1, whereas hypochlorous acid has a Cl atom in state
+1. Hydrogen and oxygen don't change.

Cl2 + H2O --> HCl + HOCl

Regardless of mechanism, yes, try to keep these molecules out of your
respiratory organs.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Coltography <http://www.reddit.com/user/Coltography> 1 point 6 hours ago

So what about all the watervapor we breathe in?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Almustafa <http://www.reddit.com/user/Almustafa> 1 point 18 minutes ago

Our lungs are really moist, we breathe out a lot more water vapor than we
breathe in.

See: your breath on a cold day.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
minno <http://www.reddit.com/user/minno> 3 points 5 hours ago

Since your lungs are warmer than the outside air, it won't condense, so
you'll just breathe it back out again.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
moocow2024 <http://www.reddit.com/user/moocow2024> 4 points 5 hours ago

Every time you exhale, your breath is almost saturated with water vapor.
Healthy people are more than capable of handling inspired water vapor.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
LaxBouncer <http://www.reddit.com/user/LaxBouncer> 199 points 6 hours ago

This is going to sound silly.... when you say heavier than air, do you mean
if I breathed upside down it would help evacuate it?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
ChainBlue <http://www.reddit.com/user/ChainBlue> 2 points 3 hours ago*

Maybe the better solution is to put yourself in a centrifuge and sling it
out. :) I believe the best option is medical treatment including humidified
supplemental oxygen.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Gideonbh <http://www.reddit.com/user/Gideonbh> 4 points 4 hours ago

One time I was watching an Adam Savage video about breathing in Helium
which makes your voice higher pitched because it's less dense than air, and
Sulfur Hexaflouride which makes your voice lower pitched because it's
denser than air. The helium naturally floats out of your lungs eventually
and your voice returns to normal but in order to fully get the sulfur
hexaflouride out of your lungs to raise your voice to normal, you have to
stand on your head a bit. Apparently it's perfectly safe though.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
BigBizzle151 <http://www.reddit.com/user/BigBizzle151> 4 points 3 hours ago

Well, breathe too much and it'll displace all that lovely oxygen bearing
air in your lungs causing you to pass out and maybe die if you can't purge
the sulfur hexaflouride, but just messing about with small amounts to
change one's voice and then doing the inversion trick should be relatively
safe.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
superdtg <http://www.reddit.com/user/superdtg>Aerospace Engineering |
Orbital/Flight Dynamics 280 points 6 hours ago

*scratches head* Actually, yes. It is more dense than air, so inverting
your lungs and breathing WOULD help. Might not be helpful enough to escape
most of the damage, but, physically speaking, it probably wouldn't hurt, if
you could have the presence of mind to do so under such painful conditions.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Zuggible <http://www.reddit.com/user/Zuggible> 1 point 26 minutes ago

Wouldn't a quick deep
breath<https://www.youtube.com/watch?v=u19QfJWI1oQ&t=2m15s>or two be a
faster solution? Sulfur hexaflouride (from the video) is also
significantly more dense than chlorine gas.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
enlightenyew <http://www.reddit.com/user/enlightenyew> 1 point 1 hour ago

Working in a position utilizing vast quantities of hazardous chemicals,
which are inerted with nitrogen, the density of gas is a huge factor in
safety. Although I work with EDA, formic acid, acetonitrile, bromine and
acetone - the gas used to inert the tanks is conceptually more dangerous
than said chemicals, even though it is over seventy percent of what we
breathe every time our diaphragm moves.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
less_wrong <http://www.reddit.com/user/less_wrong> 4 points 5 hours ago

Would the difference in density really matter in this case though?
Breathing creates air currents in your lungs, which may be significant
enough to ignore the smaller factors such as a difference in density.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Equolizer <http://www.reddit.com/user/Equolizer> 3 points 5 hours ago

If you'd move all the gasses in your lungs with every breath you'd be
right, but you're actually just breathing about 500ml (~17 fl. oz) per
breath. About 30% of the air on the bottom of your lungs doesn't move a lot
while breathing normally, so the chlorine would probably stay inside your
lungs for quite a while.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
letsgetdowntobizniz <http://www.reddit.com/user/letsgetdowntobizniz> 2
points 2 hours ago

Sorta unrelated, but should people routinely (like once a week or
something) invert themselves for a little while to allow any traces of...I
dunno... heavier-than-air-bad-gases...to be breathed out?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Almustafa <http://www.reddit.com/user/Almustafa> 1 point 20 minutes ago

Small amounts will defuse out just fine. It's only really a problem when
there's a lot of it, and/or it kills you quickly.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Equolizer <http://www.reddit.com/user/Equolizer> 2 points 2 hours ago

Well I guess that kinda automatically happens when you lay down to sleep.
You wouldn't need to turn upside down to get those heavier gases out,
laying flat on your back/stomach would suffice as the heavier gases would
then spread to the top of your lungs (meaning the top when standing
upright) and be exhaled.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
less_wrong <http://www.reddit.com/user/less_wrong> 4 points 5 hours ago

But doesn't the incoming air cause significant stirring/mixing of the "old
air"? Or am I wrong here?

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I_W_M_Y <http://www.reddit.com/user/I_W_M_Y> 2 points 57 minutes ago

Not so much with a heavier gas in your residual volume.

Just think of it like water in lungs , it sinks to the lowest parts and it
just don't dislodge very easy.

Remember chlorine is 2x the weight of O and N, and a mustard gas molecule
is about 32x the weight of O and N

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Not1MoreWordTonight <http://www.reddit.com/user/Not1MoreWordTonight> 58
points 5 hours ago

Silly question, part II. But if it's denser than air, wouldn't there be a
larger amount of it closer to the ground? Therefore being inverted and
closer to the ground would be bad? Or are we talking about breathing in
chlorine gas, leaving the room full of chlorine gas and THEN being turned
upside down?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
themostlegit <http://www.reddit.com/user/themostlegit> 1 point 35 minutes
ago

Chlorine is 4.5x as dense as air. Protocol in a cl2 leak is to get to high
ground.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
vinsoviet <http://www.reddit.com/user/vinsoviet> 16 points 5 hours ago

When I was a life guard our "chlorine gas leak drill" consisted of - pick
up nearest child as high as you can and run like hell. Picking up the
children as high as you can was supposed to get them above the gas which
supposedly would creep out along the ground. Would it have mattered? Shrug.
We never had a leak.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Terkala <http://www.reddit.com/user/Terkala> 10 points 1 hour ago

Yes, it would have actually helped. Chlorine as stored for use in swimming
pools is usually stored at ground level (due to weight). Since Chlorine is
heavier than air, it wouldn't push the chlorine very high, but it could
probably get over-the-head of a small child.

There may be some small concentration of it that gets kicked up to
your-head-height. But it would be far less fatal than being at head-height
of 3ft.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Eslader <http://www.reddit.com/user/Eslader> 5 points 5 hours ago

wouldn't there be a larger amount of it closer to the ground?

Yes. This actually was an issue as far back as WWI. There would be a gas
attack, and soldiers who were doing what you should do in a normal attack -
namely being as low as possible to avoid getting hit - would come out much
worse than the soldiers who were standing or in a higher-up emplacement.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
superdtg <http://www.reddit.com/user/superdtg>Aerospace Engineering |
Orbital/Flight Dynamics 125 points 5 hours ago

I think the only thing silly about the question is to consider the
circumstances. You are breathing chlorine (mustard gas). Burns on every
exposed surface of your body, plus your lungs, eyes, nose, mouth, and
throat, and you want to know if turning upside down will help.

That is not meant as a criticism at all. Your questions are perfectly valid
in a hypothetical sense. You have the facts correct concerning density
correct.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
Eslader <http://www.reddit.com/user/Eslader> 116 points 5 hours ago*

Just a small niggle - chlorine and mustard gas are two different things.
Mustard gas is Bis(2-chloroethyl) sulfide.

It has somewhat different effects - both chlorine and mustard gas are lung
irritants, but while chlorine is corrosive, mustard gas is a blistering
agent.

It also tends to stick around longer than chlorine - it'll get into the
soil and can still cause damage to people several days after it's deployed,
whereas chlorine gas goes away pretty quickly.

Somewhat ironically, one way to stop the blistering from mustard gas
exposure is to pour chlorine on the area.

And a bit of trivia: There's another kind of mustard gas made with nitrogen
instead of sulfur. This stuff would then become the first chemotherapy
drug, called "Mustargen."

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
OccamsAxe <http://www.reddit.com/user/OccamsAxe> 5 points 1 hour ago

Which one did the German scientist who had also invented a method of
pulling nitrogen out of the air use during WW1? I seem to recall it being
chlorine.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
therealdannyking <http://www.reddit.com/user/therealdannyking> 3 points 1
hour ago

That would be Zyklon A <http://en.wikipedia.org/wiki/Methyl_cyanoformate>,
developed by Franz
Haber's<http://en.wikipedia.org/wiki/Fritz_Haber#World_War_I>laboratory.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
VIPriley <http://www.reddit.com/user/VIPriley> 21 points 3 hours ago

Chlorine will not stop the blistering. Bleach is typically used to oxidize
the mustard and neutralize it. If you get skin contact with mustard
typically you can wash it off with bleach or another strong oxidizing agent
hopefully neutralizing it. Once you start getting blisters though its
already too late (24hrs later they develop) they are the result of a
chemical burn due to mustard. The blisters eventually will go away, but
mustards really can damage DNA so expect to eventually die of cancer.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
she_did_what <http://www.reddit.com/user/she_did_what> 2 points 34 minutes
ago

this might lean towards being an etymology question, but as a simpleton
subscribed to this sub to learn things - when you say 'mustards really can
damage' I assume you mean the mustard gases, which have no relation to
mustard seeds / food right? ... are mustard gases meant to smell (briefly)
like mustard; is that why the name ?

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
xxHourglass <http://www.reddit.com/user/xxHourglass> 1 point 15 minutes ago

Mustard gas is so named because of the yellow colour, it's not related to
mustard seed or mustard plants or anything like that. Completely unrelated,
besides the fact that they're both yellow.

[–]<http://www.reddit.com/r/askscience/comments/1qm8be/why_is_chlorine_so_effective_in_killing_anything/#>
fwump38 <http://www.reddit.com/user/fwump38> 16 points 2 hours ago

If you get skin contact with mustard typically you can wash it off with
bleach or another strong oxidizing agent hopefully neutralizing it.

Technically you forgot the word "gas." When you get skin contact with
mustard usually you can just wipe it off - no bleach required!