Supposedly life on earth is not a mere coincidence, but the chemistry of our planet is unique in its ability to create life. What is so special about H20 that makes it essential to life? It is: -polar -quite lightweight -high heat of evaporation -high energy capacity -cohesive Among many, many other things..
You missed what is by far the most important factor: The solid is less dense than the liquid - a very unusual condition. (Think of the candle you may have made from liquid wax with surface sinking down as solid takes less volume than the liquid.) If ice were denser than the liquid, it would settle to the bottom of rivers, lakes and even the ocean, at least back when not so salty.* Then liquid water on Earth would be very rare - possibly a little thin layer of ice cold water in the tropics on top of very thick ice. I doubt that any liquid water would exist at anytime, anywhere on Earth, when one considers the high albedo of ice. Also the IR loss to space would be much greater as H2O vapor is by far the most important "Green house gas" in the atmosphere and would also be very rare. Given these two facts I would not be the least surprised to learn that no spot on Earth, except locally due to some brief volcanic activity ever got above 0 degrees C. --------------- *Ocean would be nearly pure (salt free) ice as the salt in the oceans now has been delivered to them by rivers, which would not flow if ice sank in liquid water. Rain would probably not exist anywhere on Earth. BTW very low rain is the definition of a desert - it does not need to be a hot place. The entire Earth would be an extreme desert, if ice sank in water.
The definition of a desert is a region that gets less than ten inches (250mm) of rainfall per year. San Diego is desert. There are desert regions in Saskatchewan. There are even arctic deserts, we just don't usually talk about them that way.
I am surprized that 2cm/month is still a desert. Where is your defintion from? Any way when I said Earth would be an "extreme desert" I had in mind less than 1 cm per YEAR!, any where on Earth, if ice sank in fresh water. Except local volcanic activity I bet no where else on Earth would get above freezing, not even on the equator, if ice sank in 0 degree C fresh water. I.e. the most important thing about water for life to arrise is that it floats.
pH? Do you mean: -high energy capacity .........? anyone ever wonder where the 'heat' of a body (98.6) comes from? see diatomic molecules then notice what the p680 structure is;.............. as it is a method of noticing how the "energy upon mass' is stored see, what makes the p680 such an oxidizing agent (some suggest the O2 of the earth comes from this reaction of 'water' by the p680) Energy capacity as well the ability to maintain diatomic structures The energy of them diatomic structures is being meaured and was proposed quite some time ago http://www.sciencedirect.com/scienc...serid=10&md5=79ca3cc36c87580d78bb4a73c8da8fb2 here is more on the energy of diatomics http://hyperphysics.phy-astr.gsu.edu/hbase/molecule/rotrig.html#c3 http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/hosc.html http://hyperphysics.phy-astr.gsu.edu/Hbase/thermo/electrol.html h2o is a monster because of the energy storage of the structures (life is all over the universe)
here is an interesting clip http://www.i-sis.org.uk/water3.php The importance of water to living processes derives not only from its ability to form hydrogen bonds with other water molecules, but especially from its capacity to interact with various types of biological molecules. Because of its polar nature, water readily interacts with other polar and charged molecules such as acids, salts, sugars and various regions of proteins and DNA. As a result of these interactions, water can dissolve those substances, which are consequently described as hydrophilic (water loving). In contrast water does not interact well with nonpolar molecules such as fats, oil and water don’t mix. Nonpolar molecules are hydrophobic (water-fearing). and notice the energy is so important?
exactly! but then again, we have to be open to science! i wonder if out there, the community intends to call it "dark chemistry" that 'don't matter' and the 78% percent of it; just don't exist. Please Register or Log in to view the hidden image!Please Register or Log in to view the hidden image! but you have to BELIEVE!
No DRZion meant, I hope, what he correctly said: "POLAR" I.e. H2O molecule has both the two protons on one side of the O-- ion. (spread apart by 105 degrees due to the quantum mechanical lay-out of the "orbitals.") This means that side is permanently + charged and other is permanently - charged. This is why the dielectric constant (80 if memory serves) is so high. in non-polar molecules you must both induce some polariity and orient it. Rarely can you induce the polarization that is natural to water. NO - a pure nonsense idea. body temperature is tightly controlled by many different biochemical processes. Some, if acting alone would lower it and others would raise it. 98.6 (37 C) is their compromise. For many birds, which need power for flight their body temperaqture is higher ~105 F even as chemical processes likie metabolism can proceed more quickly at a higher temperature. I.e. the "comprimise temperature" of their confliciting needs is higher. Body temperature has nothing to do with water's structure. This seems very confused and I did not see any page numbers in your three links, but they are good discussion of their subject. Although this not much discussed in your references it is true - much more than you realize why, I am sure. Water has one of the highest heat capacities that exists. This is in part because unlike the CO2, which is the linear molecule: O-C-O water has all three rotational axies with significant monents of inertial ( one of CO2's is very tiny) so there are more ways to store rotational energy in water than CO2 as slightly discussed in your references but that is no big deal explaining heat capacity differences. The main reason is that water is polar and polimerizes. I.e. true formual for water is nH2O, where "n" is any of set of small integers and constantly changing with thermal collisons. That average "n" of the set decreases with temperature I.e. you ar breaking the bonds between the longer chains (larger "n") strings (and other 3D structures these polar molecules can form). The negative O-- end of one h2O molecule tends to stick between the two 105 degree protons of another. To crudely illustrate in false linear format with an individual H2O represented as: ++-- then the n = 3 polimer chain is: ++-- ++-- ++-- When water gets to be 4 degrees C, some of these polimers are much longer, like: ++-- ++-- ++-- ++-- ++-- ++-- ++-- ++-- ++-- an n = 9 example, but of course they are not straight. 4 degree water is mess of various n-values sort of like short random cut lengths of cooked spaghetti. Although the average length of any particular n long polomer is thermally contracting, the average n is increasing and the tangled mess of "spegheitti" has voids which are growing larger. -Why water EXPANDS as cooled down from 4 to 0 C. There are some n = 5 ++-- ++-- ++-- ++-- ++-- polimers at room temperature but soon they will break and others will form to keep the n distribution set invarient at any temperature. Near boiling even n = 3 is rare. Thus as you heat water only a part of the energy makes the molecules go faster on average (That is what temperature is.) part of the supplied energy is used to lower the average n of the polimer set. Thus to get one degree thermal increase in temperature for a gram of water (the definition of heat capacity) you need more heat than normal non-polar substances to break bonds. -Why water has such a relative high heat capacity. This is much more important than the fact that water can store rotational energy in three rotation axies as you seem to have understood and was vaguely implied in your reference. They were not really concerned with cause of water's high heat capacity. They were trying (quite well I add) to explain simple molecular structures and related rotational and vibrational spectral, without getting into the complexities of their interactions etc. It get rougher if you want to know why there are two "branches" of the spectra etc. (One is called the "R branch" and I forget name of other, just now.) I should note that what I have explained above is not entirely accepted by all. - Often not even discussed in college level courses. They tell your, falsely IMHO, that the formula of water is H2O instead of nH2O. But they can not explain any of water's three unusual proberties either. (1) ice floats, (2) highest non phase change heat capacity, (3) high dielectric constant or if they do note it is naturally polar, not why it relaxes so slowly when field is tured off, especially if cold. (n is larger and randomization takes longer.) SUMMARY: Water is very complex.
very unlikely - See my just posted discussion of water. Main problem with that POV is there is no known stable structure of the constantly forming and breaking up sets of n water compounds (nH2O) that could "remember"even a tiny fraction of its history. I.e. the set of n that exists and the structure of water is set by the temperature alone if there is no structre which is stable against the 10s of thousands of thermal collisions each second. The distribution of n and possible sturctures with any n value is a dynanic steady state function of temperature.
thanks for the guestimation 104.5 but is said to change with H30 and OH+ (pH levels) which you just contradicted one minute water is constantly polar, the next rarely can you induce it what happened? and as you discount the idea for people to inquire about the exothermic reaction of the diatomic O2 and H2 (a heat kicker) yu post "non-sense" but have no idea what them 'tightly controlled' processes are..... which is a really bad statement to make if you trying to stay credible, even within your own peers. so it is true, but you ASSume before even inquiring. :shrug: which of the four forces of nature is 'heat' ....? heat capacity? do you pour heat into the water? Perhaps lower the atmospheric pressure to make it boil (even at room temperatures)? non sense the environment is what to measure of 'thermal collisions' (ie..... the heat required to boil water is dependent on the atmospheric pressure of the specimen h2o) also note that the pH or energy capacity is highly affected by what OTHER elements are involved (ie...add salt to water and the water retains a greater amount of energy)
So yopu don't know what 'heat capacity' means (its taught to school kids here in the UK) so you make yourself an arse by having a go at Billy because you don't understand. The heat capacity of a material is the measure of how much energy it takes to raise or lower a unit mass by a unit of temperature. Water requires 4200J per kg per degree C. Nothing to do with the forces of nature, this is basic thermodynamics. So basic kids learn about it in school so they can make their own calorimeters. I'm sure you'll come back with something like "Do you think I don't know what heat capacity is!!!" because you hate it when someone points out your ignorance but if you do know about it, why say something utterly different to Billy? Either you knew about it and deliberately trolled or you didn't know about it but trolled for having a go at Billy because you didn't know about it. Nice one.
so you make yourself an arse knowing i don't go to BT for anything He jumped in with a foolish post (kind of exactly what you just did) then will it take more 'energy' via a flame to raise the temp of a cup of water, than it will to microwave it? WHY? Is the wavelength 2450nm the 'heat' induced by a microwave? is the microwave more efficient when imposing the 'energy' in the correct wavelength? that is easy to dispute by simply being causal as to what HEAT itself is that is the mental block you are having. What is the "blank' causing the mass to vibrate? but calories (caloric) of Lavoisier was discounted by the community as being relevant to physics. I can make water boil without adding 'heat' simply by changing the 'pressure' doesn't that tell you something? It means; 'heat' is not a property but an effect observed. the thread in on water, the life giver and for some reason, all i did was state what is already found true; Originally Posted by Bishadi h2o is a monster because of the energy storage of the structures and let it be known, i claim; you have no idea why!
Thanks for the support. - I like to teach and knew from prior experience that he could not understand my post 12, but some others may learn from it. Typically discriptions of water are very inadequate. That is why I made post 12. (It is not really a reply to Bishadi - that is useless given his sever limitations.) Bishadi is so confused, ill-equipted to comprehend, that he is best ignored, as I usually do, unless he provides an opportunity to educate others without appearing to preach or climb on some soapbox.
Billy T, so no matter which of us claims to be correct, i am happy to see that 'others' were your purpose of the post. now, you have me bowing! :bawl: thank you thank you thank you for clarification to the thread; Billy T is sharing what get's you thru your course work and the taught methodology within today's chemistry. (thank the teachers) and the idiot me, is combining a few disciplines that unveils the underlying principles (light (em) is the energy between all mass) i am learning more, from these interactions each day, to better describe (combine) what math has already proven (mass, energy, time; the transition does exist) ie...... i claim life exists based on the how nature (mass and energy associate), not by the 'chance' of magic or uncertainties (the current mechanics) thanks BT for doing what you believe is right 'for others' over any other motive. (what a beautiful thought to walk around with today)
While true, saying that the bond angle is a result of the orbital layout is kind of redundant. The reason the bond angle is 105 degrees is mutual repulsion between the protons. The angle would be 90 degrees (and water would be even more polar than it already is), but the protons are too repulsive to get that close to each other. Contrary to what many books inaccurately claim, water is not an sp3 hybrid.
Certainly the electrostatic interaction between the two protons is why the orbitals are not the 90 degrees one might expect if it were absent, but the Hamiltonian includes ALL the energy terms and then the "sp3" hybrid orbitals come out that way, so I would not call labeling the orbitals that "inacurrate", but it is just a name. One could think of them as "perturbed sp3 orbitals." There are many similar cases where one speaks of "resonances" or mixes of two different sets of orbitals to achieve a lower energy state /configuration / than either alone. But again that too is just a name; however, giving a name both helps with understanding (or at least promotes a "warm fuzzy feeling" that one does) and speeds comunication.
