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Author Topic: What's The Difference Between Hard & Soft Water ?  (Read 5434 times)

Offline neilep

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Dear Waterologists,


When I was a yoof !...we had one of these !



It's a water softener !....it's a thing of beauty is it not ?

I recall having to fill the thing with bags of salt every so often !

So that I can feel young again ...please reveal to me the nature of hard and soft water ?...and why is soft water preferable ?...does hard water have no advantages at all ? (besides being able to beat softy water up in a fight !)

Why the need for so much salt ?....and why the need for domestic water softeners nowadays anyway ?...can't they soften the water before it enters water pipe fun ?



I asked my neighbour by sticking a hose through his letterbox and letting the tap run for half an hour...I then played ' Pooh sticks ' and stuck my question on a twig which I let float down his hallway....I haven't received an answer yet but his prized tropical fish I think might have known but they were too lazy to respond.....instead they were just seen floating in a relaxed chilled out kind of way upside down !!!


If ewe know
Please do tell
My neighbour said
"go to hell"

But as he sank
Deep you know
I'm sure he meant
To say 'Hello '



Such talented poemage !!

Thanks


neil
Water Asker




 

Offline ukmicky

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What's The Difference Between Hard & Soft Water ?
« Reply #1 on: 24/07/2008 02:15:33 »
Hi Neil as this has been sitting their festering for so long i thought i would give you a half answer .

Hard water contains high levels of calcuim and magnesium and Calcium reacts badly with soap (fatty acids) preventing soap from working properly .  So by introducing a fitration system which contains salt (sodium)its possible to cause the calcium ions in the water to swap places with the (salt) sodium ions in the filter which softens up the water causing lots of lovelly bubbles to cover your modesty when you jump out of the bath after a  giant spider drops in.  I HAVE EXPERIENCE IN THAT MATTER

To be honest i'm rather more interested in knowing where all the spiders that somehow get trapped in my bath come from as there is no holes or anything above.

 I reckon they drop in from another dimension, maybe i should ask someone who knows a bit about  web theory or is that string theory.

« Last Edit: 24/07/2008 02:17:58 by ukmicky »
 

Offline lightarrow

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What's The Difference Between Hard & Soft Water ?
« Reply #2 on: 24/07/2008 13:08:41 »
Hi Neil as this has been sitting their festering for so long i thought i would give you a half answer .

Hard water contains high levels of calcuim and magnesium and Calcium reacts badly with soap (fatty acids) preventing soap from working properly .  So by introducing a fitration system which contains salt (sodium)its possible to cause the calcium ions in the water to swap places with the (salt) sodium ions in the filter which softens up the water causing lots of lovelly bubbles to cover your modesty when you jump out of the bath after a  giant spider drops in.  I HAVE EXPERIENCE IN THAT MATTER

To be honest i'm rather more interested in knowing where all the spiders that somehow get trapped in my bath come from as there is no holes or anything above.

 I reckon they drop in from another dimension, maybe i should ask someone who knows a bit about  web theory or is that string theory.


Remember that spiders too are initially very little (and they are not mammals!) and then they grow...
 

blakestyger

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What's The Difference Between Hard & Soft Water ?
« Reply #3 on: 24/07/2008 17:32:30 »
One advantage of hard water is that it is essential for the brewing industry - that's why breweries (the best ones) are in hard water areas (limestone) like Burton-on-Trent. It scales up everything inorganic that it touches - a disadvantage.

I remember years ago reading that there are higher instances of heart attacks in soft water than hard water areas -  so that's a disadvantage, though I can't remember the mechanism for this.
 

Online Bored chemist

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What's The Difference Between Hard & Soft Water ?
« Reply #4 on: 24/07/2008 19:28:28 »
I'm not sure they ever established the reason why people in soft water areas had fewer heart attacks.
Some breweries go so far as to "burtonise" the water. Burton-on-trent is widely held to have the best water for brewing. Some other breweries treat their water to make it similar to that from Burton.
 

Offline chris

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What's The Difference Between Hard & Soft Water ?
« Reply #5 on: 03/08/2008 12:21:35 »
"Hardness" comes in two flavours:

"Permanent hardness" is the presence of calcium and magnesium ions in solution. These can interact with soaps to form scum, the brown tide-mark that forms in the bath, and also a tea tide-mark in your mug.

In the case of soaps this occurs because the soap molecules consist of a fatty acid associated with a sodium ion e.g. sodium stearate, which is a consequence of the way they are made by saponification - the reaction of a fatty acid with sodium hydroxide.

When the soap mixes with soft water the two components separate and the sodium ion dissolves and the fatty acid finds some grease to interact with. It uses the fatty acid tail to lock onto oily molecules and the water-loving acid group to help them to dissolve.

But, when soap mixes with hard water, the sodium is displaced by calcium which has twice the charge (2+) compared with the sodium ion (1+). Consequently any calcium present can bind two fatty acids rather than one, but this means that the fatty acids now cannot use the acid part of their molecule to interact with water to help them dissolve. As a result they have to hang around with other calcium-bound molecules as an oily scum.

"temporary hardness", on the other hand, is the presence of dissolved calcium bicarbonate - Ca(HCO3)2. This is a problem for two reasons. Not only is it a source of calcium ions, but the bicarbonate, which is soluble, will also decompose with heating, breaking down to produce water, CO2 and calcium carbonate, the latter being insoluble limescale. This is what furrs up pipes, pans and elements.

A water softener works by exchanging the calcium and magnesium ions in the water with sodium ions. This solves all the problems, including the temporary hardness, because sodium carbonate is still soluble.

Chris

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What's The Difference Between Hard & Soft Water ?
« Reply #5 on: 03/08/2008 12:21:35 »

 

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