Chemistry of common things

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See Doughs, batters, leaveners


Trees, O2, CO2


On bottled water

Demineralized and distilled water

The difference

  • Distilled is nearly-pure H2O, because distillation means you move the water and leave behind most other things
  • demineralized means few to no minerals (fresh natural water has some, tapwater has a more-controlled bunch; see also hard water) by some method
...but says little about what else may still be in there
it's useful to keep minerals out of chothes irons, car batteries, and such (mainly to avoid limescale)

Contaminants in demineralized water

Demineralized water often mentions it is not fit for consumption

largely because depending on the process of demineralization, there may be other things still left in there, say, a few bacteria. Your iron or battery won't care, but you might
and because it doesn't matter for the intended uses
(also in part because it's also sold in supermarkets, so it's useful, possibly required, to point this out explicitly)

In practice it's usually pretty clean water, but it's not guaranteed to be.

On nutritional deficiency:

In theory there are additives in tap water, mostly a few minerals/salts, some which we need, some less so. Most common are calcium, sodium and magnesium (calcium may be there already depending on the water source).

The idea of adding fluorine has some of its own footnotes (some intro below).

These minerals won't be in distilled water or in demineralized water.

But water isn't even near a daily recommended dose of anything (other than water itself, pedants), it only somewhat helps as a backup of minerals you may temporarily eat less of(verify).

Still, if you structurally drink only distilled instead of tap water, you may need to pay a little more attention to what you eat. Which is why generally you wouldn't want to.

On water poisoning

tl;dr: You are at negligible risk.

Water poisoning happens when drinking a large amount in a short time, because of other balances, primarily salt and other electrolytes.

Basically, drinking a lot of water means shifting various balances, basically diluting various things with water containing little else, and doing that enough causes effects like osmosis taking necessary salts out of your kidneys.

(roughly why saline solution is medially a sensible way to deal with dehydration - though studies show there are subtler choices for that; 0.9% saline solution, while is already mostly water, still has more Na and Cl than human serum)

The thing is that quickly drinking liters of almost anything will do this, unless it happens to be a very specific mix.

And there's little variation in types of water, because while tap water has more minerals (including salt), as does a lot of bottled, it's almost always very low, aimed at being minor suppliment at best.

This because it's primarily salt in our food is what helps keep our salt balance, and your cravings will typically guide you near a good balance (actually, many of us eat a little too much salt).

Long story short, everything else being equal, e.g. not being stranded in the desert for weeks with liters to drink and nothing to eat, drinking the same amount of distilled or tap water has very little effect either way.

Hard water

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

Hard water refers to water having relatively high mineral content.

Typically mostly calcium, which often comes naturally from the water source passing through limestone, chalk or such. Which gives you things like calcium and magnesium carbonates, bicarbonates, and sulfates.

We're talking parts per million here - soft water is on the order of 30ppm, hard water on the order of 150ppm.

So is soft or hard water better?

It's a few different practical considerations, none hugely important.

Harder water is perfectly healthy, and arguably slightly preferable for drinking water, but is less ideal for industrial processes, and for washing machines, and means you need more detergent (or a detergent that contains a water softener), and deposits limescale in washing machines, kettles, showers, glasses, and such.

Arguments for either

"this water tastes nicer" - you probably prefer what you're used to, whichever that is.

Arguments for softer

Arguments for harder

softer water will pull out metal out of pipes over time, corroding unlined metal pipes more quickly

Putting aside that there are a handful of other factors on corrosion speed, relatively speaking harder water tends to be a little nicer on metal pipes, so makes water infrastructure a lot cheaper (and more practical, when you don't have to dig up half the country) to run, particularly if that infrastructure is currently older, cheaper pipes. -->

Fluoride in drinking water

Drinking seawater