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'Very, very pink' tap water in Alberta town

citynews.ca

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Re: 'Very, very pink' tap water in Alberta town

#41

Post by stagbeetle »

lqdc13 wrote: post #36
stagbeetle wrote: post #25

Earlier quoted context omitted.

No, but muriatic acid does. I'm pretty sure it's a redox reaction.

How is HCl related to KMnO4? And why would one combine them? Why not just add a hypochlorite to water if the end goal is to disinfect with chlorine?

It was a comparison on par with the parent comment's argument. Looking back, it wasn't well constructed on my end and probably led to confusion.

What I was going for was: just because they do the same thing doesn't mean they're the same at all.

HCl + KMnO4 -> KCl + MnCl2 + Cl2 + H2O

Re: 'Very, very pink' tap water in Alberta town

#42

Post by stagbeetle »

jcranmer wrote: post #31
stagbeetle wrote: post #18

Earlier quoted context omitted.

I would not use livestrong as a source. If the pictures are true to the situation, the concentrations are tiny. You can look up videos of people putting less than a teaspoon into water to get the same result. IIRC, PP can be a precursor to chlorine. But, you're comparing two different chemicals here and what applies to one likely doesn't apply to another. There is a chance your skin will feel like it's burning if it'…

> IIRC, PP can be a precursor to chlorine. Converting KMnO₄ to Cl¯ would require a nuclear reaction. Chlorides are generally soluble, so it's not going to cause an insoluble salt to slowly dissolve as a permanganate salt precipitates instead. It does appear to be a stronger oxidizing agent than Cl₂ (and Cl¯ and ClO¯ and ClO₂¯), but there are likely better reducing agents in most water than dissolved chlorine ions.

My wording was vague, you'll have to excuse me.

Re: 'Very, very pink' tap water in Alberta town

#43

Post by jcranmer »

lqdc13 wrote: post #36
stagbeetle wrote: post #25

Earlier quoted context omitted.

No, but muriatic acid does. I'm pretty sure it's a redox reaction.

How is HCl related to KMnO4? And why would one combine them? Why not just add a hypochlorite to water if the end goal is to disinfect with chlorine?

The allegation is that KMnO₄ is undergoing a redox reaction with HCl to produce Cl₂ gas (which is a plausible redox reaction, given the half-reaction potentials).

But yeah, in practice you're going to disinfect with Cl₂ gas or NaClO. The water plant I worked at switched from Cl₂ to ClO¯ as primary disinfectant, and the operators were all for it. No more need to manually switch out Cl₂ tanks, no more Cl₂ venting issues (spilling NaClO is nowhere near as bad a Cl₂ leak). (The plant also used O₃ for bonus disinfection as well. The operators hated it at first, but now would throw a conniption fit were it broken).

Re: 'Very, very pink' tap water in Alberta town

#45

Post by asafira »

sunnyhacker wrote: post #44

I have always wanted to buy a countertop water distiller for home use. Guess I found another reason to justify the purchase =)

Piggybacking on this a bit: does anyone have a good recommendation for learning more about home water distillers and RO systems? Both for just certain faucets and maybe even the whole household? I know filtering all the water at home is likely overkill (in most places!), but I'm curious.

Re: 'Very, very pink' tap water in Alberta town

#47

Post by cjmoran »

spraak wrote: post #38
refurb wrote: post #7

Not the end of the world. You can buy potassium permanganate tablets to purify drinking water.

Bad drinking water IS the end of the world. Nonchalant cliches like this make the right to drink clean and clear water seem like something that is mostly fairly applied throughout the world.

The pink water is safe to drink.

Re: 'Very, very pink' tap water in Alberta town

#48

Post by hwillis »

anigbrowl wrote: post #32
personjerry wrote: post #22

Earlier quoted context omitted.

Not sure if you misunderstood the article. The article indicates that potassium permanganate is what caused the water to be pink. The commenter is explaining that potassium permanganate is harmless and usually used as a water purifier anyway. I have no idea how that can be interpreted as "Oh that's absolutely demonstrably awful, here's X to subsidize your life,"

Not sure if you misunderstood the poster you replied to. People don't want pseudoscientific rationalizations for why their preferences don't matter, they want the basic as-pure-as-possible H2O that they paid for.

randomdrake didn't read the article, and saw the top comment was "you can buy tablets to purify water". He assumed, completely incorrectly, that the commenter was suggesting that people should just buy tablets to purify their water. randomdrake was not trying to comment on how essential services should always be held to exacting standards and that any failure. They weren't trying to say that it is unacceptable for water supplies to have even harmless, temporary inconveniences. They just didn't read the article.

Re: 'Very, very pink' tap water in Alberta town

#50

Post by hwillis »

spraak wrote: post #38
refurb wrote: post #7

Not the end of the world. You can buy potassium permanganate tablets to purify drinking water.

Bad drinking water IS the end of the world. Nonchalant cliches like this make the right to drink clean and clear water seem like something that is mostly fairly applied throughout the world.

He's not suggesting people buy potassium permangranate to purify their water. He's saying that the substance that is making the water pink is what people use all the time to purify water. That makes the assertion by the local government that the water is safe much more believable.
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