At what rate does scent travel through water? And how would scent be detected in still water?
437920
As scent is made up of particles then its movement through water (assuming that the particles form a colloid) would be completely dependent upon the rate of movement of the water itself. Scent could only be detected in completely still water if either a mechanical detection device or a biological sensor was placed in direct contact with one of the molecules. In animals this would be through a set of receptors that identify the molecule and send a message to the relevant area of the brain via electrical impulse.  Technically there would be a small degree of dispersal in still water due to differences in concentration  forming a concentration gradient but this would be so small as not to count.
709582
off the top of my head i think osmosis involves water moving from areas of high concentration to low ones while diffusion is a general term for molecules moving from high to low concentration.
953822
Think about the relative concentration gradients of specific solutes. You clearly wouldn't infuse something that would cause water to move out of the vasculature into the brain, you would want something that would do the opposite.
148737
Contrary to the above answers, you could smell in space. However you would need a really strong smell to do so. \n\nUs humans need to draw large amounts of the air that  contains an odour through our nose in order to be able to detectit. Space of course contains no air, so to be able to smell anyhting in space the odour itself would need ot be very concentrated.\n\nBut certainly if I opened a bottle of ammonia 3 inches under your nose in space you would smell it just fine.\n\n>>>>>But in space, there is no atmosphere for them to\n>>>>> disperse in, so there is no way for the "smelly"\n>>>>> particles to diffuse to your nose.\n\nUnless the gravity is EXTREMELY dense , the smell is EXTREMELY faint or the the conditions are EXTREMELY cold those molecules will diffuse faster in space thanon Earth.\n\nAs they are liberated from the source they must have achieved vapourisation temperature. Therefore they already have significant velocity. The odour molecules will be colliding with each other and undergoing all the normal interactions. As they disperse more the velocity will remin unaltered but the movement will become linear rather than random brownian movement as they cease to interact. But that would only make the dispersion faster, not slower.\n\nIf you don't believe me consider this. If you placed a bowl of water on the surface of the moon what would happen?  If lack of an atmoosphere stops volatile molecules from dispersing how does the water evaporate in space? Now what would happen if you placed a small amount of ammonia in that water? If the ammonia molecules are dispersing far enough to allow evaporation then why would they not disperse further?\n\nFor all those who said that you can not smell in space this is the critical quetsion to answer. If you accept that ammonia, chlorine and other odoriferous materials can evaporate in space why dont you also believe they are capable of diffusing?\n\nAnd if you believe they are capable of diffusing why do you believe the ofactory glands couldn't react to them?\n\nAnd if you believe the olfactory glands could react to them wwhy do you believe that the neurons couldn't pass that to the brain?\n_______\n>>>>>This answer more pretains to solid 'smell' particles\n>>>>> rather than 'smelly' gasses.\n\nI'm not quite sure what that means. The only 'solid smell particles' are things like smoke. I'd guess that 99.9% of the odours humans detect are gaseous: perfume, ammonia, body adour, food and so sorth. All are caused by volatile materials, ie they exist as gas when we smell them.\n\nYou are correct that the tiny number of odours actually caused suspended solid particles could not travel readily in a vacuum. But most odours would travel further and faster in a vacuum.
780024
Diffusion is the normal migration of molecules from an area of higher concentration to an area of lower concentration until and equal concentration is achieved.  Everything in nature does this.\nExample-open a bottle of perfume then pretty soon the person in the next room can smell it and so on.\nOsmosis is diffusion or the movement of water across a semipermeable membrane( a cell membrane that lets some stuff in and keeps others out.).  It can go in or out of the cell based on the concentration.  Water is a common carrier molecule for other substances.\nThus diffusion and osmosis are the same except osmosis must have a membrane crossed.
289697
At room temperature and 1 atmosphere of pressure air is much less dense than water.  So, even if the molecules in air/perfume are moving at the same rate as those in the water/alcohol mixture, the perfume molecules will go farther before they collide with an air molecule.  Thus, perfume in air will diffuse much faster than alcohol in water.  \n\nBTW, I must correct blackdragon's comment that alcohol does not mix with water.  Most common short chain alcohols, such as methanol (wood alcohol), ethanol, and isopropanol mix well with water.  Ethanol is the alcohol in beer, wine, and other alcoholic drinks.
117333
Because of it's wave-like characteristics.\nSame thing happens to sound.  Travels faster in water than in air.  If you are underwater, and you hear a firecracker go off in the air above you, when that sound is passes to the water, the water molecules being more dense, will transmit it faster.\nNo more energy is added, nor does it pick up energy, but the medium vibrates at a faster frequency with the same amount of energy.\nThe amount of energy a wave has does not correspond to the speed at which it travels.
819069
I got this from my physics prof.  Take a full glass of water, preferably a wine glass, and and some food colouring for the water.  Take a clear piece of acetate and cut it in a circle for the top of the glass.  The piece of acetate needs to be larger in circumference than the glass though.  Place the acetate on top of the glass and turn the glass over.    Explain why the water doesn't escape.  The answer might surprise you.  A hint is because of pressure but how much is there, where does it come from, and what is its dimension?
852474
scent is hard to quantify. \nUsually you have to figure out its components e.g by using gas chromatography or mass spectrography. Then you can figure out the amount of each substance present. \nAlternatively you can measure scent by the reaction of an organism to it, e.g. how much you drool if you smell your favorite food. But that also means the reaction of the organism depends a lot on the scent and organism chosen. For example a male moth will react to one molecule of the pheromone the female moth gives off. I don't know if humans can even smell that stuff.
273925
The simplest way is spectography. if you are speaking of a breathalizer test it is via conductivity.
241031
Actually, to correct a previous answer, waves in water travel faster than waves in air because the propagation velocity is proportional to the medium density. \n\nSounds produced by a gas modulating larynx are bubbled out of ones mouth underwater. Acoustic energy is transferred from air to water as they emerge from the mouth. there is an impedance mismatch at this point. Also the shape of the bubble emergence guarantees that this is not a very linear transmission mechanism. The result is nonlinear attenuation and spectral dispersion which results in muffling of the signal.\n\nIf you were to use an underwater transducer (speaker) and send your acoustic signal (using a mic and amplifier above water), the intended receiver would hear it with good fidelity since there is no gas/water boundary to cross in this scenario.\n\nHope this helps
965419
Yes; think of the cell as a sack filled with stuff surrounded by a semipermeable membrane. Water diffuses through the pores based on its concentration. That is, water goes from an area of great to less concentration. Since the distilled water by definition has no solute and is 100 per cent pure and since the concentration of the water in the cell is diluted by the presence of small particles (almost one percent), water flows from the outside to the inside very quickly. The membrane is stretched so much by the infusion of water that it bursts.
788216
Smell is based on the nose detecting the presence of molecules. If the smell is coming from an object there must be molecules coming from it. Whether that results in a loss of mass depends on how they are being released.\n\nIf the smell is from molecules on the surface of the object just floating free into the air, then yes it does lose that mass.\n\nIf the smell is due to molecules being released in a chemical reaction with the air or other surrounding substance, then the reaction *may* actually add to the object's net mass. Or it might not. It depends on the nature of the particular reaction.\n\nIn most cases I'd think it would be just molecules floating free so it would lose mass.
461298
you observe it at room temperature.\n\nyou can do this by :\n\n1. smelling it ( it smells like clorox or a swimming pool.\n\n2. run it thru water- it will bubble and dissolve causing the water to smell like the above.\n\n3. use chemical analysis to confirm the gas is chlorine at room temp.\n\nhope it answers you question ( unusual )
1101435
Smell, or olfaction, as scientists call it, is an important sense for many fish. Those little holes that look like nostrils are called nares. Nares don't lead to the throat the way nostrils do in mammals, but open up into a chamber lined with sensory      pads. Not all fish move water in and out through these nares in quite the same ways, but key to a strong sense of smell for fish is the ability to move water rapidly over these sensory pads. Some fish can pick up chemical signals when immobile by      pumping water through their olfactory system via tiny hairs called cilia. Other fish can pump water by a muscular movement. Some fish, such as smaller species of mackerel, have an olfactory system that requires them to swim in order to get water      moving through their nares. When the sensory pads pick up chemical signals, they transmit them to the fish's forebrain, which interprets the signal and incites the fish to respond appropriately.
498363
why it gets sweaty? there's a good physiological answer but i don't think that's what you're really after.\nwhy do you want to smell it? the same reason you shared this question with us and the same reason we answered.  humans are way too curious, just ask the cat.
115707
It depends on the pressure and temperature of the water so the previous answer is limited to only one condition.