But nuclear fission isn't a chemical reaction?
But nuclear fission isn't a chemical reaction?
The problem with all these descriptions is that they don't offer any insight or real understanding.
Describing atoms as a package of protons neutrons etc. is like defining water as a colourless, ouderless, tasteless liquid. While it may serve some purposes, it doesn't provide a deeper understanding of what water actually is.
So what's the difference between an electron and an atom? Why do we perceive collections of atoms as solid & electricity as not?
>>The problem with all these descriptions is that they don't offer any insight or real understanding.<<
This is because of the arbitrary nature of the core definitions/assumptions within science as a whole and the jargon inherited by it from older systems of thought.
'Atom' simply means 'indivisible' (I think Democritus is credited with the notion and word: atomos). For science 'indivisible' is just great for classical/pre-20th century physics, but is not so good for 20th/21st century science because radioactivity blows a hole (sometimes literally) in the concept of 'indivisible', not to mention the reality smearing of quantum theory (ie topography/geometry of energy levels whether of nuclear or atomic material is described in terms of probability - there is no absolute boundary between what 19th Century science would have considered as absolute and separate chunks of matter: atoms).
So you're back to a dynamic and arbitrary definition again - because it changes to suit the paradigm/belief of the moment.
With regard to you job interview, presuming it was for a scientific position, it would be wise to stick to a 'standard' or current definition along the lines of the smallest unit of matter/energy that can participate in chemical reactions. Better still, play the game of rhetoric and point out that it can have a variety of meanings and throw the question back. If the interviewer fails to appreciate the possible meanings of his/her question then it's probably a good point to wish them every success in finding someone who is suitable for the job as you are, unfortunately for them, far too knowledgeable to waste any more of your valuable time in their Company.
Note: Chemistry may be regarded and is sometimes described as, 'Atomic' physics, dealing as it does almost exclusively with the electromagnetic force (radiochemistry aside) - photons and electrons; neutrons and protons (nuclei) are just chunky bits that provides a convenient descriptor for mass and a useful balancing act for electronic charge.
I like CShot's answer the best, though.
Code:class Electron { }; class Proton { }; class Neutron { }; class Atom { Proton* pptr; Electron* eptr; Neutron* nptr; }; class Molecule { Atom* aptr; };
Couldn't think of anything interesting, cool or funny - sorry.
Funny Onion!
Ken Fitlike isn't too far wrong. I'm doing my chemistry degree now and the nucleus could just be a dot as far as I'm concerned ( organic chemistry aside ). I can however tell you all about the lovely shapes of probabalistic electron density clouds. My first lecture course was on quantum mechanics.
"Chemistry is based around the electron, therefore to understand chemistry you must understand the electron".
http://uk.geocities.com/ca_chorltonkids
that would be a nuclear reactionOriginally posted by Nick
But nuclear fission isn't a chemical reaction?
that would be because electricity is the motion of electrons from one atom to the next think of it as a fire squad where every atom passes on the electron to the next one...Why do we perceive collections of atoms as solid & electricity as not?
Last edited by ZerOrDie; 10-19-2002 at 06:10 PM.
An atom is simply a catagorization describing groupings of smaller particles. Interestingly, there are not 3 but 2 of these smaller particles! The neutron split yeilds a proton, an electron, and a photon! In turn, the electron may simply be a 'bound' photon, and if all of the above are correct, then the true 'particles' are reduced to protons and photons(quanta of light).
As far as chemistry is concerned, reactions cannot make any changes to the nucleic structure of the atoms involved. That is, when you burn somthing, nothing changes on the atomic level, merely on the molecular (aside from stripping electrons). However, if too many proton/neutron pairs are grouped into a neucleus, the atom becomes unstable and splits into somewhat equal halves, resulting in a very sizable release of energy and some mass loss(fission). Alternately, if you superimpose nucleic matter, you can cause it to not merely split, but almost fully convert to energy(fusion). The most interesting fact about atoms is that they are mostly reused. We are literally made up of the mountains and rivers of the earth!
Also, with electricity, it is not that the electrons are passed along, rather, the vibrational intensity and frequency excite neighboring eloctrons to respond in kind to their neighbors. So I suppose with electrocution, you are actually shocking yourself to death
Code:#include <cmath> #include <complex> bool euler_flip(bool value) { return std::pow ( std::complex<float>(std::exp(1.0)), std::complex<float>(0, 1) * std::complex<float>(std::atan(1.0) *(1 << (value + 2))) ).real() < 0; }
>>Ken Fitlike isn't too far wrong. <<
That's a relief. Sorry, for 'energy levels' read 'particle density distribution'.
>>I'm doing my chemistry degree now<<
I finished with chemistry so long ago that it was called 'alchemy'
>>organic chemistry aside<<
nmr? If so, then covered by electromagnetic force.
>>I can however tell you all about the lovely shapes of probabalistic electron density clouds<<
Oooooh! You'll go far! It takes that something extra (in my opinion anyway) to get excited by orbital symmetry. Good luck with that degree!
>>As far as chemistry is concerned, reactions cannot make any changes to the nucleic structure of the atoms involved. <<
Radiochemistry? (Thus my description, "the electromagnetic force (radiochemistry aside)". Nuclear transitions involve weak (radioactive decay) and strong nuclear forces. )
Here's one for cold fusion, first proposed (late 1950s?) by Andrei Sakharov (USSR physicist and dissident): Take a couple of deuterons (heavy hydrogen), replace the electrons with mesons (negatively charged like electrons but more massive) and sit back and watch as the wonderfully wierd quantum world makes its presence known. Since all 'particles' exist in a superposition of states and that their 'density distribution' can only be measured in probability, the chances of two hydrogen nuclei in a diatomic hydrogen molecule ever being close enough together, at a moderate temperature, is vanishingly small. By replacing the electrons with mesons and bumping up the mass number of hydrogen to deuterium, the probability of nuclear fusion ie 'overlap' of the nuclei, while still very low, is realised.
>>fact about atoms is that they are mostly reused<<
...and is the original object orientated language (which Endo has already alluding to). Is this why there seem to be a lot of proto-chemists/chemists/former chemists here at cprog?
If one considers an ion to be an atom, (I don't - an atom is uncharged a charged "atom" is an ion), and one accepts that an H+ ion is simply a proton, (i.e. a Hydrogen nucleus), and we accept that H+ ions can be involved in chemical reactions, and we say that a proton is smaller than any atom, then does it not follow that a nuclear particle, the proton, is the smallest particle that can take part in a chemical reaction?
Where the hell is Clyde when you need him?
Wave upon wave of demented avengers march cheerfully out of obscurity unto the dream.
Chemical reactions are per-force polaric. Therefore, the electron is the smallest participant in chemical reactions (and the most active initiator due to it's speed and freedom). The proton is almost 2000 times more massive than the electron, thus it is slow and heavy.
I finished with chemistry so long ago that it was called 'alchemy'
Nice analogy there.>>fact about atoms is that they are mostly reused<<
...and is the original object orientated language (which Endo has already alluding to). Is this why there seem to be a lot of proto-chemists/chemists/former chemists here at cprog?
Code:#include <cmath> #include <complex> bool euler_flip(bool value) { return std::pow ( std::complex<float>(std::exp(1.0)), std::complex<float>(0, 1) * std::complex<float>(std::atan(1.0) *(1 << (value + 2))) ).real() < 0; }
>>H+ ion is simply a proton<<
Only in plasma. In solution the free proton doesn't exist (well maybe for an infinitesimal duration...), it's solvated eg in water as H3O+.
>>then does it not follow that a nuclear particle, the proton, is the smallest particle that can take part in a chemical reaction?<<
Already covered by "This is because of the arbitrary nature of the core definitions/assumptions" ie it is whatever you state it to be, provided all subsequent measurements and observations are made from that perspective.
But consider that this hypothetical free proton interacts with other matter: it abstracts an electron, or rather interacts to produce some other stable/meta-stable 'compound'. Which leads to:
>>the electron is the smallest participant in chemical reactions<<
Similar to the free proton but also can exist solvated eg in ammonia (NH2-) where it forms a beautiful blue colour.
For those looking for a standard/working definition, then definition 3a of this atom seems utilitarian enough.
I realise the H+ attaches to one of the lone pairs on the water Oxygen, however, the chain of reasoning came about when I read this from the thread...
>>> atom: the smallest particle of matter which can partake in chemical reactions.
...it struck me that this was not an adequate definition.
I think part of the problem with this thread/problem is that we are trying to fit todays understanding of matter into an old fashioned terminology framework - the foot is bigger than the shoe.
Wave upon wave of demented avengers march cheerfully out of obscurity unto the dream.