How does the surface tension of rainwater differ from that tap water?How does it differ tension of cooking oil
361682
Dissolved minerals in tap water and surfactants such as oil reduce the surface tension, so rainwater being the most pure should have the highest surface tension.
1169843
What I hear when pouring water from one cup into another (trying to maintain the same flow rate and height) is a more distinct sense of pitch and more loudness in the burbling of the cold water compared to the hot. Note that this effect is most detectable when the hot water is in fact right at the boiling point.\nThe main mechanical difference between the two is the water's vapor pressure, and the hotter water has a higher vapor pressure, reducing surface tension and making cavitation more possible. The dissipative effect of cavitation may account for the apparent reduction in sound intensity and ringing.
1057705
A liquid is one of the four main phases of matter. It is a fluid whose shape is usually determined by the container it fills. Liquid particles (normally molecules or clusters of molecules) are free to move within the liquid volume, but their mutual attraction limits the ability of particles to leave the volume. The volume of a quanitiy of liquid is fixed by its temperature and pressure. If this volume is not exactly matching the volume of the container, a surface is observed. The surface of the liquid is behaving as an elastic membrane, in which surface tension appears. Due to this effect, liquids form drops and bubbles. Capillarity is another consequence of surface tension.\n\nLiquids exert pressure on the sides of a container as well as on anything within the liquid itself. This pressure is transmitted in all directions and increases with depth.\n\nIf a liquid is at rest in a uniform gravitational field , the pressure &#92; p at any point is given by\n\n    &#92; p=&#92;rho g z\n\nwhere:\n\n    * &#92; &#92;rho = the density of the liquid (assumed constant)\n    * &#92; g = gravity\n    * &#92; z = the depth of the point below the surface.\n\nNote that this formula assumes that the pressure at the free surface is zero, and that surface tension effects may be neglected.\n\nLiquids generally expand when heated, and contract when cooled. Objects immersed in liquids are subject to the phenomenon of buoyancy.\n\nLiquids at their respective boiling point change to gases, and at their freezing points, change to solids. Even below the boiling point liquid evaporates on the surface. A liquid will evaporate until the concentration of the vapors belonging to the liquid reach an equilibrium partial pressure in the gas. Therefore no liquid can exist permanently in a vacuum.\n\nVia fractional distillation, liquid components from a mixture can be separated from one another as they vaporise at their own individual boiling points.\n\nGlass at normal temperatures is not a "supercooled liquid", but a solid. See the article on glass for more details.
222634
Tap water evaporates as it sits around.  The additives become more concentrated as the water evaporates but they don't dissipate.  Eventually they "precipitate" as salts and end up as solids in the container.
341668
Water evaporates at 100 degrees, celsius, so the liquid water you touched wouldn't be any hotter than that. The metal, on the other hand, does not. So it would be as hot as the object which is heating it.
1183757
Oil is less dense than water.
204425
Water cycle is enhanced in the tropical area. Why? Higher temperature, more direct sunlight, water evaporates faster (the warmer air can hold more water vaper than cold air w/out condensing).
1140715
1. surface tension of water. See the different surface tension of different liquids in different containers, e.g. test tubes, beakers, glass, etc... Another is look at the surface tension of water at the glass or beaker, would a thread, pin , paper would float? And when a detergent powder was added what would happen?\n2. geology, look around, look around the environment, are the rocks the same? gather as many as possible rocks and differentiate each of them. In other words classify them.\n3. Do an investigatory project about the faces of the moon, draw them.\n4. Give or look for evidences or proofs that the earth is round.
663820
It may be surface tension.
754572
surface tension is a surface phenomenon shown by liquid surface to acquire least area,\nit is the force in newtons acting tangentially perpendicular along one metre.\n\ngravitation is attracting force which is acting on two masses
852848
Because its water and a raindrop wil make a mm difference and not a centimeter, I'm not 100% sure but is common sence.
108781
Surface Tension = An attractive force between water molecules called hydrogen bonding.
501766
I agree that it is emulsion.  Oil is less dense than water and will remain on top of the water.  They don't mix so it isn't a mixture.
421576
Here's an interesting article that explains a little about how surface tension works in droplets.\n\n\n"Surface Tension in Water Droplets \nIntermolecular forces create the surface tension that causes these water droplets on leaves to bead up and form the smallest surface possible. The water molecules at the surface are pulled in by the cohesive force between themselves and molecules inside the droplet. The water keeps its droplet shape because there are no water molecules outside the surface to balance this inward pull. "\n\nhttp://encarta.msn.com/media_461560536_761563983_-1_1/Surface_Tension_in_Water_Droplets.html\n\nHere's another resource,\nhttp://en.wikipedia.org/wiki/Surface_tension
947544
It sounds like you're talking about water dripping (rather than flowing) out of a faucet.  \n\nEach droplet will continue to grow in size until its potential energy due to gravity equals (or rather, just barely exceeds) the total surface energy (surface "tension", as we often call it) of the spherical surface that would exist if the droplet were in free space at that instant.\n\nSince the volume (and thus the mass, and thus the potential energy) of each spherical droplet increases as a function of its radius cubed, whereas its surface area (and thus its total surface energy) increases as a function of its radius squared, the above event is inevitable.  And since gravity and the density of water are essentially constant, the critical size of each droplet is likewise.\n\nWant bigger drip-droplets?  Go to the moon, where gravity is weaker.  \n\nI hope I answered the question you were actually asking. :P\n\nEDIT :: And by the way, the connection between my answer and the one immediately prior to mine is that the water droplet's surface energy is governed by the strength of the dipole bonds between its molecules.
636488
Different oils have different boiling points.
818083
Rainwater will have a pH determined by its composition.  Its composition will be water (pH=7), O2, CO2, SO2, NOx,... stop me when I've mentioned something that strikes you as a product of human pollution.  There are some ultra left wing radical commie pinko pseudo scientists who LIE about pollution and say it is a GLOBAL problem.  But WE all know that we can fowl our rivers and burn our forests and nothing will be affected more than oh a couple of feet away, right?  RIGHT?!! Tha tha thats all folks.