[Swiifty]

Greetings!

Me and my friend were discussing how they got to know the different structureformulas for molecules. You know, their formation, for example metan CH3-CH3, how they're connected in real life.
I said that they used some kind of microscope and did a lot of "general" research :p and my friend replied that it is impossible to view a real life molecule as they microscopes aren't able to zoom down to such level.
Now my question is kind of obvious but anyway. How did they discover how the molecules look in real life? Is it today possible to take a "picture" of a molecule?

Thanks in advance.

[Borek]

Your friend is wrong - it is possible to "see" single atoms, although not in the case of ethane.

http://en.wikipedia.org/wiki/Scanning_tunneling_microscope

Many structures can be researched using so called X-ray crystallography

http://en.wikipedia.org/wiki/X-ray_crystallography

This method allows exact determination of atoms positions in crystal. The only problem is you will need a crystallic ethane

[AWK]

Crystal structure of ethane is known

[P]

Your friend is wrong - it is possible to "see" single atoms, although not in the case of ethane.

http://en.wikipedia.org/wiki/Scanning_tunneling_microscope

Many structures can be researched using so called X-ray crystallography

http://en.wikipedia.org/wiki/X-ray_crystallography

This method allows exact determination of atoms positions in crystal. The only problem is you will need a crystallic ethane

I think the friend means optical instruments in which he is correct.  The Scanning Tunneling Microscope (same for the similar Atomic Force Microscope) act like a blind man reading Braille  -  they 'FEEL' the surface. Even so - you can as Borek said 'SEE' the individual molecules with these instruments.

[Borek]

"To see" when it comes to using microscope is very confusing.

artcile with parasite picture

Do you "see" this parasite, or not?

I think we should use "see" in a flexible way. Even assuming that we should use "see" only when the medium is visible light doesn't isolate us from troubles. What if we use light amplifiers? If I am looking at the picture on my monitor - can I still say I have "seen" something?

This is one of these cases when there is no sharp and obvious border between what we "see" and what we don't. Just like you can't classify everything as either white or black - some objects are gray 

[Custos]

How did they discover how the molecules look in real life? Is it today possible to take a "picture" of a molecule?

In reality we do not know what molecules look like in "real life" and, thanks to the Heisenberg uncertainty principle we never can with any great precision. At the molecular level our understanding of ethane is an averaged out, or probabilistic, description of where the protons neutrons and especially the electron may actually be. Even the X-Ray structures are not true pictures of the molecule but calculated models based on diffraction patterns. As chemists we get so used to drawing representations of molecules that help us understand reactions we sometimes forget that these are just models - not true representations of reality.

No it is not possible to take a picture of a molecule. A molecule is not a static entity; rather it is a spinning, pulsing, vibrating particle. It can be described mathematically, it can be represented as a model, but it cannot be visualised in the sense of taking a picture.

[P]

"To see" when it comes to using microscope is very confusing.

I think we should use "see" in a flexible way. Even assuming that we should use "see" only when the medium is visible light doesn't isolate us from troubles. What if we use light amplifiers? If I am looking at the picture on my monitor - can I still say I have "seen" something?

This is one of these cases when there is no sharp and obvious border between what we "see" and what we don't. Just like you can't classify everything as either white or black - some objects are gray 

    I compleatly agree.

artcile with parasite picture

Do you "see" this parasite, or not?

    that's a bit scarey!!   I dont like spiders!! 

[AhmedEzatAlzawalaty]

there has been recently alot of work on HNMR and CNMR and Mass spec. X-Ray Crystallography,IR ,UV  and if u studied these issues u would know how we discover the structure of any molecule.