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I am studying different means of collecting water for consumption. From resources available on Internet, I understand that distilled water is not advised for regular consumption because of the lack of minerals and salts, while rainwater can be consumed if not overloaded with unwanted chemicals.

What confuses me is that I know water to be pouring down from clouds, which is water vapor turning into droplets through condensation. To me, this looks to be exactly the same as the process of distillation, i.e. evaporation and condensation of water.

So is my assumption about rainwater formation wrong? What is the difference between rainwater and distilled water? What causes this difference to happen?

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While there are some internet memes that advise against drinking distilled water, there is no real problem with doing so. The minerals in most water are only ever present in very small amounts with barely measurable effects on health (very hard water is known to marginally lower heart attack rates) so their lack is not going to be significant either. – matt_black Nov 4 '12 at 0:05
@matt_black: perhaps you would be interested in this discussion then,… – Benjamin Nov 4 '12 at 8:57
Not everything on skeptics is reliable. Read Rex Kerr's answer and the comment about the provenance of the study that supposedly proved it. Or read my answer to this question and see some proper statistics on the small differences to people caused by different mineral contents. – matt_black Nov 4 '12 at 10:08
Agreed. Nutrition is a tough science, because it's just tough to experiment, since manifold ingredients end up to make big soup in the body. Not even mentioning metabolism are not all the same. BTW Do you know a way of remineralising water other than adding a package of minerals? – Benjamin Nov 4 '12 at 14:13
""way of remineralising water other than adding a package of minerals?"" ROFL – Georg Mar 21 '15 at 20:52
up vote 13 down vote accepted

Rain water passes through the atmosphere and picks up whatever is present there, including particulates such as dust, trace amounts of atmospheric gases, nitrates and nitrites, and so forth.

Rain water is relatively low in mineral content. In practice, people drink rainwater from streams and wells, where it has had ample opportunity to pick up minerals from soil and rock.

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The YouTube channel minute earth even explains why it is impossible for rain to form without dust or minerals in the middle of each drop, but sadly I can not post the link at the moment. – Aubrey Champagne Nov 28 '15 at 3:19
Do you know of better sources for this than "lmgtfy"? Well-regarded published papers, for instance. It would also help for this answer to include some quantitative information - both rainwater and distilled water will contain some amount of impurities in practice, so what we really care about is how much. – Nate Eldredge May 12 at 22:11
@Nate: There are several well-regarded studies in that Google Search. I'm happy to enumerate all of them in my answer, but the Google Search is maintained and updated automatically. – Robert Harvey May 12 at 22:32
Indeed. But part of the purpose of SE is to get answers from experts. Google can tell us what studies there are, but it can't give us an expert opinion as to whether they are relevant, reliable, appropriately conducted, etc - that's where you come in. There's also a preference for answers which are not "link-only" but give a summary of the conclusions, thus helping to avoid link rot. – Nate Eldredge May 12 at 22:36
W@Nate: Well, I'm not actually an expert, but I do know enough about the rainwater ecosystem to answer the OP's question at his level of expertise. If the OP wants detailed composition analyses (he didn't ask for them), then someone else is probably better qualified to render those. Properly distilled water really shouldn't contain anything in significant amounts except water molecules, though I suppose you could contemplate copper atoms picked up from the condensation tubing. – Robert Harvey May 12 at 22:38

Rain water contains very low amounts of salts and other nitrates but it takes in any gas present in air. That is why acid rain occurs when the air is polluted. The air contains oxygen so people recommend the rain to be consumable as it has lots of oxygen contents in them. But distilled water does not contain any minerals in them, so it is not recommended for consumption because of lack of minerals.

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hello sir benjamin

The three gases (nitrogen, hydrogen, oxygen) exist at the same proportions, 3 equal volumes. The volume of hydrogen is combined in whole with ½ volume of oxygen to form all the water from the ground, which explains its absence in almost air. ½ of the remaining volume of oxygen formed the ozone layer and the breathable O2 representing 21% of the air current, nitrogen is known by its inertia to respond, which explains its abundance (78% of 'air).

A-Primary water origin on earth:

The land was originally a ball of molten material, she played the same role as that played by the sun now that is to say a nucleosynthesis until the formation of nuclei of oxygen because it has been designed or formed by accretion in a space where the hydrogen prevailed, when the earth cools, the law reverses, the heavier atoms will take to downdrafts whose atoms (O) and light atoms will escape into updrafts whose atoms (H) s' unite into molecules (H2), the mechanical strength of these updrafts and downdrafts carried around the ground allow the combination of these two gases in incessant explosive chemical reactions (synthesis of water) with a heat generation, all current waters on earth were formed and hydrogen was totally consumed, as it unites with ½ to 2 volumes Volume oxygen is what explains its almost non-existent in the current air the remaining ½ volume of oxygen will form ozone and O2, which explains its proportion (21% air) the abundance of nitrogen (N2) in our atmosphere (78%) is due to its inertia to react it only reacts to 300 ° with the hydrogen to form NH3 in a reversible reaction N2 + 3H2-->2NH3 and 2NH3--> 3H2+ N2, that is to say that it will release easily the hydrogen will combine with oxygen to form water again until exhausted. Is it likely that this temperature was reached or even exceeded account keeping heat from the exo-therm synthesis water. (H2+ O--> H2O + heat), the result is always the same.

B- Rainwater (new hypothesis):

1-Photolysis (dissociation or photolysis) of ocean water consists of the decomposition of the water molecule into hydrogen molecules (H2) and carbon (O) under the effect of solar radiation in the ultraviolet occurrence.
2 -molecules (H2) and atoms (O) are driven by the currents of warm air upward and drythat generate mechanical force, which opposes that of the cold air downdrafts, thereis an opposition two mechanical forces of compression where the volume of air including a mixture of oxygen in the form of atoms (O) and hydrogen in the form of molecules (H2) which both agitated by the fact of compression, friction and the effect of solar rays ionize (hydrogen is charged with positive electricity and oxygen with negative electricity, it is also known very electro-negative); once a favorable compression ratio achieved, the two gases combine in an explosive chemical reaction (synthesis of water is explosive), they form water (H2O). 3-The light of the flash reaches us first (299,792,458 m / s), second the sound of the explosion was thunder (340 m / s) and finally the rain fall rate which is lower to those of the light and sound. So lightning + thunder + water = are at the same time in one operation

Occurs between 2000 to 5000 frames per second And each storm cell can cause more than 100 flashes per minute This means that rainwater is formed by chemical reaction itself around the earth 200000-500000 times per minute, it is rainstorms but there remains a significant amount of water vapor suspended in the form of clouds driven by winds which will then form by coalescence regular rain without lightning or thunder but the initial origin of its formation remains the same. If rain water was forming as we learned it would have really enjoyed in summer (since evaporation is greater) in winter and so-called positive charge cloud is none other than ionized hydrogen and negatively charged cloud of ionized oxygen. Any cloud is formed of a plurality of water molecules that are themselves in bipolar as a mist (therefore speak of positive and negative cloud).
Steam arises from collisions between H2O and after release by photolysis but its life is very short, it suffers the same fate that is to say, the photo-decomposition by ultraviolet, and releases its constituents, H2 and O continue their ascent to the cold front.

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There are a couple of problems with this answer. Tell me where to start. – TIPS Dec 22 '15 at 20:12
Please blockquote portions of the text that you used word for word. Also, references should be used to illuminate your answer, not comprise the entire post. – jonsca Dec 23 '15 at 1:12

protected by jonsca Dec 23 '15 at 1:11

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