Do elements have odor, and those elements, in certain combinations, create the smells of the world?
If elements have odor, do we know what each one smells like, (for example, what does hydrogen smell like, or nitrogen?) Or, do only molecules, created out of atoms have the ability to create odor?
I assume that smell has to be carried at the atomic level, but I’m not exactly sure if I’ve ever heard or read anything that explains this. But odor has to be carried some way from the object to our nose, and that smell has to be made up of something, so at the basic level, I would think that each element has to have an odor of some sort.
Am I on the right track, or is there some other explanation?
Your nose is a chemical sensor, with zillions of cells sensitive to different molecules. Only specific molecules or ones very similar to them will bind to the cell’s receptor sufficiently to trigger a nerve impulse sent to your brain. Some (perhaps most) elements are odorless. You can certainly smell sulfur, chlorine, bromine, iodine, phosphorous, and other elements, but for all I know this is because of reaction products of those elements.
Most of what you smell, and taste are complex molecules. I am not sure that we (the Royal we) smell at an atomic level, but we certainly smell, and taste, by extension certain chemical compounds.
Actually as I understand it that’s how pheromones work, not the substances we actually consciously smell. That old lock-and-key model fails to explain how we can often smell synthetic molecules that aren’t like anything natural.
IIRC, the modern viewpoint is that the olfactory tissues have a great variety of sensors, each variant reacting with greater or lesser strength to a wide variety of molecules. So when you smell something, what is being identified is the pattern of which sensors are being stimulated, and how strongly. So something that has little similarity to a substance can smell the same as long as it happens to stimulate a similar pattern.
Some do, some don’t. Chlorine, for example, has a distinct odour that most people can recognise immediately. In contrast Nitrogen or Helium or truly odourless. Metals are also technically odourless, but because they react with components of the the cell they still trigger an odour reaction. So you can detect copper by smell, but technically it remains odourless.
No, it’s much more complex than that. Once elements combine to form compounds they react with your olfactory receptors in totally different ways to the elements themselves. For a simple example, nitrogen is completely odourless, and hydrogen nearly so. But once they combine as ammonia they have an extremely powerful odour totally unlike either “parent”. At a more complex level, rancid fat and sugar are both just carbon, hydrogen and oxygen, but they have totally different odours.
So the odour of the elements is totally unrelated to the odour of the compounds the produce
Yes.
Probably not, but that’s a tricky question because the only elements that don’t exist as molecules are those that are unreactive and thus, by definition, unable to provoke an olfactory response.
But I can see no reason why, if you could hypothetically feed someone a stream of mono-atomic Chlorine, they wouldn’t be able to smell it.
As others have noted, it’s carried as a particle in the air.
And no, each element doesn’t have to have an odour. If it did then everything would have an odour, and lots of things are completely odourless.
Things only have an odour if they are volatile (ie able to get airborne) and able to chemically react with the odour receptors in your nose.
So, is it possible that our olfactory tissues pick up the same chemicals and they could possibly smell different to different people? For your example, pheromones may be what attracts us to another at a smell sensory level, where another person may not smell anything at all?
I can buy that most elements as stand alone elements are odorless, but smells are created by the combination of elements. A pizza smells much differently than a gallon of gasoline. These combinations of molecules are carried to our olfactory sensors to register the different substances. But the smell has to be created from something, right?
OK. But I’m still on the right track when I say that combinations of elements, or complex molecules creates a unique smell that is molecularly the same, even if our personal olfactory sensors pick them up differently, yes?
Another question then. If the odor is created by molecules, then at some point, the molecules would dissipate and the item would be odorless. Or would it? If I open a can of oil, the only way that stops smelling like oil is if it somehow evaporates. Is that a correct statement?
Also, how is the “odor” carried by the molecules? Is it caused by the way the molecules are arranged, and that combination provides a vehicle to carry the odor to our senses? I guess I’m not real clear on how the odor is carried by the molecule. Are we smelling electrons, protons and neutrons arranged in infinite combinations?
That’s correct. You can only smell something as long as it’s producing volatile molecules which evaporate and reach your nose. Eventually, everything stops smelling, when all the molecules that interact with your nose have been carried away.
The odour is not an instrinsic property of the molecules themselves, but rather, it’s caused by the interaction of the molecules with certain receptors in your nose. Molecules don’t “carry” odour, they *are *odour. If we were biologically different, and had different receptors in our noses, we would smell different things, and would not smell things that we currently do.
Let’s take a simple example - ammonia, mentioned upthread. Someone across the room opens a bottle of ammonia. You smell nothing - until a breeze wafts a few ammonia molecules your way. When they are sucked into your nose by your breathing in, they chemically attach themselves to particular receptors in your mucous membrane. That triggers an electrical impulse which travels up nerves to your brain, and suddenly you can smell ammonia. There are many types of receptors in your nose, each binding to a different chemical in the air. Argon, for example, does not bind to anything, so you can’t smell argon.
I’m not sure that is true. Some elements are odourless, some aren’t. I wouldn’t like to hazard agues which is more common.
If by “combination of elements” you mean “chemical composition” then, yes.
The “smell” is a sensation created when pizza molecules or gasoline molecules react chemically with the olfactory sensors in your nose.
I’m not sure exactly what you mean. You seem to be referring to qualia, and that’s a whole different story to the physical causation of smell. Smell itself doesn’t have any molecular basis. It’s just a sensation.
Yes.
Essentially yes. This is true so long as it chemically remains oil. Of course substances can also be rendered odourless by being chemically changed into something else that is odourless. This is how most enzyme odour killers work.
But so long as the oil remains chemically oil it will smell like oil until it all evaporates
I’m not sure I understand the question. We are smelling vapourised molecules. Those molecules react with sensor sin your nose, and those sensors convert that reaction into an electrical impulse that your brain interprets as smell. There is no “vehicle” for the odour per se. The odour is simply our monkey brain’s way of saying “molecule X has entered your nose”. If molecule X hadn’t entered then we wouldn’t have registered that odour.
IOW the molecule isn’t a vehicle for the odour, the odour is simply the notification of the existence of the molecule at that place and time.
OK, now you’re definitely talking about qualia, and that’s primarily a philosophical question, not a scientific one. Roses to other people may smell like what you would sense as faeces, and those other person may see red as what you would sense as yellow. There’s no way of knowing this.
Certainly there are odours that some people cannot smell, just as there are colours that some people cannot see, and frequencies that some people cannot hear. But that is completely different to odours that everyone’s olfactory tissues can pick up but that might smell differently to different people.
Related, some optical isomers smell different from each other, like carvone. These molecules have the same chemical formula and are chemically mirror images of each other, but one isomer smells like caraway (I think) and the other smells like mint. I thought that was pretty cool.
I don’t think that’s “definitely about” about qualia any more than, say, color blindness is. And I’d expect it to be quite possible for things to smell differently to different people simply because they have unusual olfactory receptors. Nor is it true that there’s “no way of knowing this”; for example, if a person says that something smells the same as gasoline and the other person thinks it smells the same as roses, we are clearly looking at an actual difference in perception.
No, it’s entirely different., as I explained at length in the post you quoted from. For your benefit I will repeat:
Certainly there are odours that some people cannot smell, just as there are colours that some people cannot see, and frequencies that some people cannot hear. But that is completely different to odours that everyone’s olfactory tissues can pick up but that might smell differently to different people.
I can’t actually figure out what this means.
How would you distinguish this from a person who is simply being unable to detect an odour? People with red-green colour blindness can’t distinguish say that some orange shades from green. That isn’t evidence that they have different light receptors. It simply occurs because they lack the ability to percieve some wavlelengths entirely.
If you have two puzzle pieces that are mirror images of each other, they won’t fit in the same place of the puzzle. (Barring varios forms of symmetry.)
I’ve heard this (and smelled it). I’m still not clear on what a smell actually is, though.
Hearing is based on sound waves. I get that.
Seeing is based on light waves. I get that too.
Smelling is based on something interacting with your olfactory glands. I understand that. What I don’t still get is what the smell really boils down to. If most elements have no smell, then we are looking at complex molecules. is it just that we are all wired basically the same way to smell an orange as an orange?
Do all mammals smell everything basically the same?
I’m assuming all animals don’t, as some can pick up scents that humans cannot (like the bloodhound, for example).
