The Problem of Hard Water and the Science behind it

What is Hard Water?

Hard Water is water with a high mineral content, usually calcium and magnesium. This high mineral content is what gave Hard Water its name; they make it harder to clean household items. The reasons for this are two fold. Firstly, the presence of heavy minerals leads to a build up of limescale on kitchen appliances, often seen on the spouts of taps and in the kettle. Secondly, these minerals cause a chemical reaction with traditional soaps that prevent them from working as effectively.

To understand why this is we have to look briefly at the science of soap. Chemically, soap is negatively charged, while the minerals in hard water are positively charged. This means that the two are attracted to one another, and, when in contact, cause a chemical reaction that changes the sodium salt component in soaps into their calcium and magnesium salt counterparts, thus resulting in a sticky residue. This chemical reaction is what prevents soaps from builing up a sufficient lather.

Hard water causes a build up in the kitchen, but it can also play havock with your hair.

The topical application of calcium (chalk) and magnesium is certainly not advisable. And yet living in a hard water area means that everytime you have a shower you are adding it to your hair and skin. Depending on the hardness of your water, this can lead to brittle, dull, lifeless hair that never feels properly conditioned. This is because the positive charges in the minerals bind to the negative charge of your hair, effectively forming a barrier between it and any conditioner you use.

Commercial Shampoos have a different chemical make up to traditional bar soaps, and so work to remove the mineral build up in the hair before conditioning. However as we all know, many of these Shampoos come full of their own nasties; artificial preservatives, colourings and chemicals. So what can we do to tackle the hard water problem if we still want to use natural, chemical free soaps?

How to soften your water

Hard water can cause a multitude of problems, but the one we hear about most often is with people switching to a natural shampoo bar. The chemical reactions between the soap and minerals in the water can cause a thick film to form on the hair, preventing it from being properly washed out. There are however a number of solutions that you can try.

If your hard water is causing problems all through the house, calcifying appliances and drying out your skin and hair, you may want to invest in a water softener. However for those who havn't got the extra cash, there is another option.

Many people suggest using a Sodium Bicarbonate (baking soda) solution to rid you hair of the mineral build up caused by hard water, with some people even using it instead of shampoo all together. While this is great for removing the mineral build up, it doesn't solve the problem of hard water, as you end up re-applying the minerals when you rinse your hair again.

To actually soften your hard water, you can use Sodium Carbonate (washing soda). Not to be confused with baking soda, the chemical formulation of sodium carbonate is Na2CO3, compared with bicarbonates' NaHCO3. Sodium carbonate is typically used in industrial cleaning and glass manufacture, however it is often found in the household for cleaning clothes or neutralising odours.

Baking soda and washing soda share many of the same applications, having the same sodium base. However washing soda has one application that baking soda does not; it binds to the minerals in hard water, changing their chemical makeup and thus making them insoluble. This is why it is also widely used as an industrial water softener.

While it is commonly used on an industrial scale, don't let this put you off. Washing soda is a naturally occurring salt that is mined all over the world, from Wyomming to Kenya.

So how do we use washing soda to soften our water? Simple, add one or two teaspoons to a bucket of water, give it a stir, and let the salt do the rest. You can filter the water after, to remove the insoluble molecules, however it might just be easier to leave it to settle and skim the top water off with a jug.

Soft Water and our Shampoo bar

Now that you have soft water you should be able to prevent the chemical reaction occurring when you use our Lavender + Rosemary Shampoo bar. Many of our customers live in hard water areas and have found that they don't have a problem using hard water at all. It all depends on the 'hardness' of your water, as the mineral content of water varies depending on your location.

Let us know if using sodium carbonate helped you or if you found that the shampoo bar worked well even in hard water. We'd love to hear your experiences!

If you'd like to see how to use sodium bicarbonate around the house, see our homemade cleaning product blog here

For more information on sodium carbonate please see the following links

Julie Ward