Water Definition and 1000 Threads

Water is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, even though it provides no calories or organic nutrients. Its chemical formula is H2O, meaning that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. Two hydrogen atoms are attached to one oxygen atom at an angle of 104.45°."Water" is the name of the liquid state of H2O at standard conditions for temperature and pressure. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor.
Water covers 71% of the Earth's surface, mostly in seas and oceans. Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (consisting of ice and liquid water suspended in air), and precipitation (0.001%). Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.
Water plays an important role in the world economy. Approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of the long-distance trade of commodities (such as oil, natural gas, and manufactured products) is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of substances both mineral and organic; as such it is widely used in industrial processes, and in cooking and washing. Water, ice and snow are also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, diving, ice skating and skiing.

View More On Wikipedia.org
Recent contents Top users
  1. G

    Calculating Heat Gained by Supercooled Water

    My argument is that heat lost by lump of mass converted to ice will be gained by remaining water. But how do I find heat gained ?
  2. H

    Boiling Tap Water for Drinking: Benefits & Risks

    Recently I have been boiling tap water, for about 30 minutes, everyday for drinking water. The reason I do it is because I don't like the taste of chlorimines and chlorine and this is the only way I know to get rid of them without also losing minerals. It works great, and in fact, the water...
  3. guywithdoubts

    Water bending with comb: but where do the electrons go?

    I suppose the stream isn't being charged!
  4. Johnnyallen

    Water pressure affects air pressure

    In the movie The Abyss an oil rig crew works and lives at the bottom of the ocean in a deep sea structure. There is a compartment where there is an opening in the floor allowing the crew to lower a submersible craft without going through any kind of air locks etc. We all should know from high...
  5. kmot

    Fluid mechanics - Linearized shallow water equations

    Hi, In a text describing solution to linearized shallow water equations, I am not able to move forward. It's a 1 dimensional shallow water setup. There is a steady state (velocity) and (height of free surface). On top of this steady state there are u' and h' as disturbances. The goal is to...
  6. Y

    Can someone tell me which formula to use here? (time to boil water)

    An amount of water at a temperature of 20 °C is passed through a water boiler in 1.5 min to brought to boiling point. The kettle is broken and does not jump off. The time between the moment when the water reaches boiling point and the moment when all the water is evaporated, is equal to: a) 7,5...
  7. S

    Do equations for groundwater flow refer to water density?

    As I understand Darcy's law, it computes the flux of water through an area. The same value of flux can be the realized by different combinations of a density of water in the soil and the velocity of that water. So. as far as I can see, Darcy's law is ambiguous about which combination of...
  8. danielhaish

    Does ice melt faster in water because helps to change the phase

    so according to this https://en.wikipedia.org/wiki/Nucleation nucleation start faster when there is a round matter that already in the phase that the other matter is going to ,so in case of ice melting in water because it would have more Nucleation points, edit: i mafe alittle experience and it...
  9. J

    Water analogy in Particle Physics

    There is something unusual about water. Without atmosphere, water can't exist. It's as if water is part of atmosphere. In vacuum, liquid water can't exist. What other things like water where it needs other aspects like atmosphere to exist? And what is the analogy of water in particle physics...
  10. I

    5G and future 6G terahertz absorbed by water vapour = heating?

    I just found this piece in an article: Terahertz waves (THz), which are submillimeter waves sitting between microwave and infrared light on the electromagnetic spectrum, have been used to achieve data rates greater than 100 Gbps. Unfortunately, THz waves share an Achilles’ Heel with the...
  11. K

    What kind of clothes should I avoid washing with very hot water?

    I don't normally wash clothes with very hot water but in order to eliminate clothes bugs I need to soak them in very hot water, as advised. I'd like to know what kind of clothes or texture should avoid being soaked in very hot or boiling water? The only texture I can think of is artificial...
  12. LCSphysicist

    Is this entropy problem right? (heating a beaker of water)

    I am a little confused why does the temperature was took out of the integration, is there an error in the solution?
  13. LCSphysicist

    Electrodynamics problem -- Calculating the resistance of ocean water

    A return path for the current was provided by the ocean itself. Given that the resistivity of seawater is about 0.25 ohm-meter, see if you can show that the resistance of the ocean return would have been much smaller than that of the cable. (Assume that the electrodes immersed in the water were...
  14. S

    Mass of vapor per hour for heating water

    I thought about using Black principle to solve this question but I am confused about the final temperature of system Q released by vapor = Q absorbed by water mvapor . cvapor . ΔTvapor + mvapor.Lv + mvapor . cwater . ΔT2 = mwater . cwater . ΔTwater But what is the final temperature of the...
  15. rxh140630

    Related rates: water level in a cone

    Firstly I'm having trouble understanding what water level means. I tried a quick google search and got the following: " water level(Noun) The level of a body of water, especially when measured above a datum line. " That doesn't help me. Is water level the distance from the base to where the...
  16. S

    What time is needed to move water from a pool to a container?

    I take position 1 as the surface of the pool and position 2 as the surface of the container so the value of ##P_1 = P_2 = P_{atm}## and ##v_1=0## and ##h_2=0## ##P_1 + \rho gh_1 + \frac{1}{2} \rho {v_1}^2 = P_2 + \rho gh_2 + \frac{1}{2} \rho {v_2}^2## ##\rho gH = \frac{1}{2} \rho {v_2}^2##...
  17. weirdoguy

    Heating up water versus water with an iron brick

    Hi guys, girls, and non-binaries. I'm a private high school teacher and I'm preparing myself to prepare others for polish physics olimpiad. So I delved into books which have a lot of tricky questions and from time to time I stumble upon one I have trouble with. And that's exactly what happened...
  18. Astronuc

    Beware of Vibrio bacteria in warm water: Gulf and Atlantic Coast areas

    Bailey's death came days after he handled crabs, one which pinched his finger causing a cut. Some vibrio bacteria entered the fresh wound into the blood stream. Since 2007, reports of illness from toxic forms of vibrio have tripled in South Carolina and nearly doubled in North Carolina...
  19. Mircro

    Radio waves in air and water - difference in path

    Hello, this is an assigment form the 4th grade high school physics in Croatia, concerning electromagnetic waves. Radio waves of wavelength 12m propagate from the source. The source is on the surface of the water and two waves propagate from it: one through the air and the other through the...
  20. jaumzaum

    Is Supercooled Silicon Similar to the Anomalous Behavior of Water?

    Does the anomalous behavior of liquid water between 0 and 4 Celsius degrees (i. e. expands while cooled) have something to do with the other anomalous behavior of ice (i.e. floats in water)? Are those behaviors correlated ?
  21. F

    Water flow rate and drip surface tension

    hello i have a drip tube with water dripping and when i increase the flow rate or frequency of drips they get bigger/more massive. i see the equation mass x gravity = 3.14(tube diameter)(surface tension) my mass is changing but not gravity, 3.14 or tube diameter so surface tension must be...
  22. Greg Bernhardt

    NASA discovers water on the moon

    https://www.nasa.gov/press-release/nasa-s-sofia-discovers-water-on-sunlit-surface-of-moon/
  23. shk

    Force and motion -- A water drop on the windscreen of a car

    Hi Please help me with part C. I have answered the question and have attached it for you to see.
  24. lamejane

    PVD Vaccum Chamber -- How to clean up after Water leakage?

    Hello all , our PVD chamber experienced a water leakage from the cruible revoler area and unfortunately we are no longer able to achieve a stable Base pressure ( ~10e-6 mbar) We do not have the option of a bake out. Is there any other way to get rid of water in the chamber ? Ofcourse the water...
  25. M

    Discover the Surprising Power of Water: Tap vs. Fire Hose vs. Pressure Washer

    Okay, so I don ' t have any real specs but i just want to know how big is the difference between water from tap versus the one from fire hose versus the pressure washer?
  26. WMDhamnekar

    MHB How to compute the energy needed to compress the water isothermally?

    Hi, Answer given is $E_n=29.4 Joules$ Here is the question. Answer provided by the Chemistry math expert/Professor is as follows but it is different from the answer given. How is that? Compressibility is the fractional change in volume per unit increase in pressure. For each atmosphere...
  27. D

    Water Phase Diagram: Mathematically Modeling and Validating

    I notice that water phase diagrams provided online always seem to show a rather linear behaviour for the solid-liquid boundary (and an extremely steep slope). How is this modeled mathematically? Say we use the Clapeyron equation with ΔH and ΔV_m being constant, as online example problems (meant...
  28. archaic

    How Does a Resistor Affect the Heating Time of Water?

    1)$$R=\frac{\Delta t(\Delta V)^2}{Q}=\frac{\Delta t(\Delta V)^2}{mc\Delta T}=8.33\,\Omega$$2)$$\Delta t'=\frac{mcR\Delta T'}{(\Delta V)^2}=\frac{\Delta T'}{\Delta T}\Delta t=59.4\text{ min}$$3) I surfed the net a bit and have found a post on physics.stackexchange in which it is mentioned that...
  29. A

    Light refracting and reflecting in a drop of water to form a rainbow

    I drew the red and green tangent lines and I found that the angles in blue are equal to theta 1. Also , as the BCD triangle is equilateral, theta 2 = 30. With this I can calculate the side of this equilateral triangle as a function of the radius R of the circumference. After that, I can't go on...
  30. S

    Solvation of Ionic compound in water

    When you dissolve, for example, NaCl in water, then you get "NaCl in water" solution. Will the "NaCl in water " solution have different chemical properties from its constituents(NaCl and H2O)? i.e. is a "NaCl in water" solution a new compound with respect to NaCl or H2O ? And is the ion...
  31. D

    What is the BTU load for a chiller to maintain a water bath temperature of 34 F?

    I have been wracking my head about this one... In other jobs I have sized chillers a few times but this one is a bit different. We have a "Bath" of water, about 400 Gallons The baths beginning temperature is 34 F 5000 lbs of product runs through this bath every hour at a temp of 40 F Roughly...
  32. Z

    Cylinder in a heat bath @ 0C contains water and ice & is compressed

    You can use the change in volume to find how much ice turned into water, and then find the energy required to melt that ice - that I have no problems with. But then work done by piston = change in internal energy of ice/water combination (which we found) + heat released to the bath. And we...
  33. S

    Will a vortex form if you pump water up via the bathtub drain?

    ... And if it won't form spontaneously with reversed flow, then will a vortex at least sustain itself once we nudge it in one direction?
  34. S

    Raising humidity - how much water is needed?

    Hello, my first post here so nice to meet you all :) I have a question. Let's take a small room, about about 16 m^3 (172 feet^3). This room has a very low humidity, especially in the winter. It is around 35%, i would like to raise it to 55% with a custom made swamp cooler. I am trying to figure...
  35. AN630078

    Biology Water Potential and Osmosis Potatoes Investigation

    a) Evaporation will remove water from the test tubes as it turns into water vapour, meaning that the solution will have a greater solute concentration and thus an increased osmotic potential which results in a more negative osmotic potential. Consequently this lowers the solution's water...
  36. DaveC426913

    Building a Cheap, Portable Water Level Recorder for Seiche Monitoring

    I want to build a cheap, portable water level recorder so I can record the "seiche" on my lake (and other lakes). I don't want to use fancy components like Arduino boards. And I want it to be portable (and cheap enough that losing it to water, weather or thieves won't be a heartbreak.) There's...
  37. N

    Density of Water at 1°C & 8°C | Homework Help

    Homework Statement:: The relative density of water is determined by the rate at which it expands (and contracts) with changes in temperature. At approximately what other temperature T does water have the same density as at 1 ∘C ? Relevant Equations:: Just looking at graphical and analyzing...
  38. S

    Friction loss in water flowing through a globe valve?

    Imagine water flowing inside this from say left to right. Energy can't be destroyed or created. Pressure can reduce due to the three 90 degree turns. Is the pressure or energy loss due to the heat or deformation or kinetic energy loss of the water to the wall inside? What must be the wall be...
  39. C

    New method of traveling on water

    My question concerns what I call R.P.S. (Rotating Planing Surfaces). This version uses freely rotating disks to plane across the surface of the water somewhat similar to wheels on a car going down the road. Specifically what the lift / drag ratio might be and will it be higher than a typical...
  40. Wrichik Basu

    Effectiveness of saline water against respiratory tract viruses

    Since the outbreak of COVID-19, many people, including some doctors, have been saying that gargling with salt water is effective against SARS-CoV-2. The theory rolled out is that the virus "stays" in the nasopharyngeal tract for some time before going into the lungs, and rinsing the tract with...
  41. jaychay

    Related rates calculus problem about a water tank

    Summary:: Consider the rectangular water tank, at the base the length is the same for 200 cm. There are 100 holes for water to come out which each hole have the same flow rate. Find the amount of water that come out in each hole by using differential when we know that there is an error in the...
  42. jaychay

    MHB Related rates calculus problem about water tank

    Consider the rectangular water tank, at the base the length is the same for 200 cm. There are 100 holes for water to come out which each hole have the same flow rate. Find the amount of water that come out in each hole by using differential when we know that there is an error in the measurement...
  43. StefanBoon

    Is it possible to have water levels at different heights without a pump?

    I wonder if air can remain trapped under a structure that has a deep and a shallow tube. I have already tested with a prototype whether increasing volume in the shallower tube works. Air bubbles came out on the short side, so this doesn't work. Is there any way to realize this concept.
  44. S

    How does valve size affect water heater pressure loss?

    There are 2 kinds of home instant bathroom water heater. The multipoint and single point (or shower heater). The latter is one where the unit is connected directly to the shower head. In the multipoint, its located a distant away and it serves multi points like sink and bath. What would happen...
  45. DaveC426913

    Bacteria, mold and household water

    I live in a house that's 91 years old. I had the pipes replaced with copper a few decades ago, but its still an old house. Occasionally, I have to unscrew the aerator on the kitchen faucet and shake out the mineral grains. They're always red (pres. iron oxide). This time, I wiped my finger...
  46. HelloCthulhu

    Chemistry Amount of water electrolyzed during PEM electrolysis

    I've been doing a little independent research into PEM fuel cells and came across this Horizon mim fuel cell. I read the following specs, but didn't see anything about the volume of water being electrolyzed...
  47. P

    Forces at the bottom of a rotating U-tube filled with water

    So when the rotation starts some water will move upwards and in the vertical part of tube. I know hat centripetal force will be given by F=mv²/r Now I though of taking r as centre of mass of the water system but I don't know what to take the value of m as? Should I only consider the water...
  48. N

    How to Calculate Final Pressure in a CO2-Saturated Sealed Vessel?

    I have a sealed vessel, it is 200 ml, it contains 25 ml of water which is then saturated with CO2 (bubbled through at 0.3 l/min unitil pH drops, ~ 1 h) at rt. The vessel is then heated to 130 °C. I wish to calculate the final pressure of the system. Thus far I have calculated the volume of CO2...
  49. W

    Why are Water and Ethanol densities specified at different temperatures?

    Why is the standard density of water given at 4°C while the density of ethanol is generally given at 20°C?
  50. jahinparvez

    What happens to thermodynamic properties when water flows through a reducer?

    When water flows from a large diameter to small diameter through a reducer, i know pressure will decrease from bernoulli eq. But what happens (increase or decrease) to the other various thermodynamic properties such temperature, enthalpy, internal energy, entropy, and specific volume?
Back
Top