Is water kind of like energy, can't be created, can't be destroyed?

Question

I remember from my youth a big "have to conserve water" campaign (during the Acid Rain scare) but I always wondered because don't we drink water and then either urinate or sweat it out and then it evaporates and then become clouds which rain and then we drink it again.
Doesn't the amount of water (overall in all forms) stay pretty much the same?

Answer 1

pretty much, yes... but the amount of "drinkable" water can change a lot if you waste it (or even if you don't : the weather can do it for you)

also, the amount of water is the same worldwide and throughout all its forms (liquid, solid, gaz). Which means that the amount of liquid water changes all the time. But it's still pretty much the same worldwide : it would need a radical climate modification to change a lot worldwide...
but locally, it can change drastically with only an anormally hot summer, for example.

Answer 2

You are talking about the conservation of energy when you say it "can't be destroyed." In general, total energy remains constant, but the forms of energy are constantly changing. When all those forms of energy are summed up, they will equal that total energy constant.

Water, on the other hand, is not "pretty much the same." Earth gets replenished with water every day by water bearing extraterrestrial bodies, like comets, that collide with it. On the flip side, water evaporates every day and some of that escapes the atmosphere; so Earth loses it. Mars is a prime example of a planet that probably once had water on its surface, but now that water is gone through evaporation into space.

Like energy, water comes in many forms called states: solid, liquid, and gas; and variatiions of those three forms (e.g., snow, rivers, and clouds). And there is a water cycle where the forms change over time and then return to their original state. You are absolutely right that water does evaporate, become clouds, rain out, and become liquid again. But the amount of water on Earth in all those various states is not constant.

Answer 3

Well, according to the first law of thermodynamics, all matter (water is made of matter) cannot be created or destroyed.

Water conservation serves many roles. Many municipalities get their water from resevoirs, so during a drought said resevoir can quickly get depleted, right? So, water conservation attempts to reduce the demand placed on the resevoir, ensuring that everyone has a supply (albeit lessened) of water.

While water does not actually get destroyed, it does get stored in different places. Unfortunately, water vapor does not just go up into the sky, condense, and fall again as rain on a single spot. Things like winds constantly move clouds/capor all over the globe. A drought occurs when the conditions for rain (an abundance of water vapor in the sky in cloud form) do not appear for an extended period of time.

Also, water must be treated by water treatment plants, right? That takes energy (provided through fossil fuel-powered plants). Less water consumption = less water treatment = less energy consumption.

I hope this helps.

Answer 4

Yes, it stays pretty much the same, but most water is in the oceans. Since salt water is difficult to process into drinking water, the " conserve water" campaign has to do with conserving fresh water. If you use take a lot of water out from underground and then it evaporates and rains down into an ocean, it becomes pretty much useless for drinking and irrigation.

Answer 5

Worldwide, it tends to stay about the same, I'd guess. But we have no way to measure the water content of the whole world, so it's kinda a moot point, wouldn't you say?

When they want you to conserve water, they're concerned with saving fresh (unsalty) water, because that's what we drink and water our plants with. Most of the water on Earth is salty, and although you can remove the salt, it's a bit of a pain. Better to not waste the fresh stuff.

Answer 6

Water is "destroyed" and "created" in chemical reactions. The number if hydrogen and oxygen atoms are conserved, but they just make up different molecules.

A fuel cell works by "creating" water from O2 and H2

That same reaction takes place in the space shuttle's main engines, the exhaust is water.

Answer 7

In one sense, what you are saying is sort of true. Water does go through this process of transformation. But, once water changes from being pure H2O to something else, it's not drinkable without further purifying. It's not that we don't have enough water available, it's the fact that we don't have too much drinkable/useable water to spare. In fact 75% of the world is water but we can only use very small fraction of that.

Answer 8

Water is one kind of energy, I think so. In Vietnam we use Water to produce energy,it's safe and cheap.
of course energy is not destroyed (you know the law of conserved energy), but water can be destroyed or created
for ex : NaOH+ HCl=NaCl+H2O
An d water do not stay mach the same. some special water (triti..) are used for the special aim

Answer 9

Water being a compound of oxygen and hydrogen,H2O, can be broken down into its elements. There is very little drinkable water in the world. Although there is a water cycle, most water is salty.Pollution of our fresh water sources is not a good idea.

Answer 10

water can be broken down into it's parts, Hydrogen and Oxygen ... water itself can be created by combining these two elements and it can also be destroyed by vaporizing water into a gas. So, to answer your question, no, water is not like energy, it can be created/destroyed but it takes energy to do this.