Chemistry Question

[IrishAyes]

Okay, at first glance this might appear to be in the wrong forum because it started with a DIY topic on another website. But those other groups don't necessarily have any SCIENTISTS, much less chemists, and I want the very best answer to my dilemma.

It all started when apartmenttherapydotcom said don't use vinegar for a softener in dishwashers and washing machines anymore because it's hell on the fittings and hoses. Since I have heard about water softener systems screwing up the plumbing in houses, that brought me to a screeching halt.

So I started looking up DIY liquid fabric softeners and except for one, ALL have vinegar in the formula. The one that doesn't says use epsom salts instead.

Question: Is the alkaline epsom salts just as bad for rubber hoses and fittings or less so? than vinegar on rubber hoses and fittings? If it is, can a real chemist tell me a better way to do this?

[Gman]

1. Vinegar contains acetic acid

A weak organic acid. I would think that by far using bleach would be much more corrosive than a small amount of very diluted acetic acid. I don't see a problem. Most pipes are plastic which doesn't corrode.

[IrishAyes]

7. Thanks!

[jeff47]

2. Biologist, so not quite a chemist

But don't worry about it.

First, rubber isn't generally used on the waste side of a dishwasher or washing machine. And the vinegar is only going to touch the waste side of the pipes.

Second, "The dose makes the poison" in all things. The vinegar you are using is very diluted. It's just not strong enough to hurt anything.

Why use vinegar at all? A slightly acidic solution can dissolve calcium deposits and a few similar salts. These are known as "hard water stains", and a weak acid can help remove them without damaging anything.

The kernel of truth is products like drain cleaner are strong alkaline solutions instead of strong acid solutions. Strong acid solutions would clear clogs a little better. But strong acid solutions can also eat cast iron pipes, which is what all drain lines used to be made of. If you used a strong acid, you had to take extreme care to sufficiently wash the acid out, or it would heavily corrode the pipes. So the people behind Draino and the like use a strong alkaline solution instead, because they can't trust consumers to wash the acid out properly.

People hear that kernel of truth, and extrapolate it to vinegar because it's also an acid. But vinegar is a much weaker acid, and you're using it at a very weak concentration.

To get a vinegar solution where you would have to start worrying about the seals and tubing, you'd have to go to a chemical supply house and get the 100% acetic acid they have. The "distilled vinegar" bottles in your grocery store are about 5% acetic acid. And then you dissolve a little of that into gallons of water in the washing machine/dishwasher.

[IrishAyes]

5. Thank you so much!

For all the info. No telling when I might need to put what to use.

So now I won't worry. Both the washing machine and dishwasher are very high capacity, and in the former I was only using about 1/8 cup in the final rinse. Baking soda and vinegar are what I put down all my household drains about twice a year, and I do flush them out half an hour later with a lot of hot water - whether I need to or not!

[csziggy]

10. A note about cleaning drains with baking soda and vinegar

I do double duty - I use white vinegar to clean my coffee maker out about once a month. When the vinegar finishes going through the coffee maker, I pour baking soda into the kitchen sink drain then pour the hot vinegar down it. With a double sink I do it in the side furtherest from the drain pipe going into the floor.

It is pretty spectacular in all the bubbling and foaming that goes on but it helps clear out accumulated grease and crud. Since I then need to run clear water through the coffee maker a couple of times to get rid of the vinegar odor I then pour the hot water from that into the drain to flush it out.

[Chemisse]

11. Great answer, biologist!

Very helpful.

[Lionel Mandrake]

12. you'd have to ... get the 100% acetic acid

100% acetic acid is hazardous in a several ways. It's also known as glacial acetic acid, since its freezing point is close to room temperature. If it alternately melts and freezes, it might break the container it's stored in. You wouldn't want to touch it, because it's toxic and can readily pass through your skin. Also, it's flammable.

You probably wouldn't want to store glacial acetic acid in your kitchen.

[Warpy]

3. While you can probably soften fittings in a strong aceitc acid solution

it's still a very weak organic acid, nowhere near the strength of inorganic acids, in a weak solution in the bottle and weaker still in your rinse water.

I use it here in NM because our water is alkaline and full of minerals, which means an acid is necessary to dissolve soap scum and mineral deposits on clothing and the machine. In the concentrations seen by the fittings as the weak acid flows by, it's not worth worrying about.

Just because you read something on the internet doesn't necessarily make it so. What you have is a weak acid in a weak concentration made weaker still in the wash.

Dishwashers are a little different. Instead of an acid, you might have better luck with a wetting agent consisting mostly of glycerine.

[IrishAyes]

6. Normally I'm not quite so jumpy.

And I'd certainly have been suspicious of anything in the comments area. But this was a regular article and apartmenttherapydotcom is supposedly well researched and reliable. Wait until I get hold of them!

Thanks, btw.

[SheilaT]

4. The first thing to ask yourself:

If the vinegar is such hell on fittings and hoses, wouldn't you have noticed everyone around you needing to replace those things regularly? Although, come to think of it, I use commercial softeners, not a DIY one, and maybe they don't have vinegar in them.

I can tell you that in all my many years of using dishwashers and washing machines I've never had a problem with the fittings and hoses.

[IrishAyes]

8. Glad to hear that - thanks!

I really appreciate everyone's helpfulness.

[eppur_se_muova]

9. Epsom salt is not alkaline, it is neutral.

If you want a better decalcifier than vinegar, try a *little* citric acid. It's sold in canning supplies -- but because it's food grade, it's kind of expensive.

Don't EVER combine vinegar or any other acid with bleach ! Maybe that's the source of the complaint about hoses and fittings ?? Not sure. But combining the two will produce (among other things) chlorine gas, which is highly corrosive. Also, don't EVER combine ammonia-based and chlorinating cleaners, as they will produce highly toxic, and even explosive, products.

BTW, most of those "rubber" hoses are probably neoprene, which is more resistant to corrosion than natural rubber. And I would think brass fittings would be pretty resistant to acetic acid/vinegar.