Jump to content

mississippichem

Resident Experts
  • Posts

    1710
  • Joined

  • Last visited

Posts posted by mississippichem

  1. That's direct evidence of something extraordinarily atypical, and I can't imagine any doctor that wouldn't want to write a paper about you if you could truly do this in a predictable, repeatable, testable way.

     

    Agreed. This is a very easily testable claim. Everyone has a stopwatch on their phone, if not then someone has a clock.

     

    questionquester, if you really have this ability you should immediately visit any general physician and show him. If they are not interested they will know others who are. You should just focus on the heart rate ability for now because it's so easily verifiable. You are either being dishonest or truly have an amazing ability. I don't know as I don't know anything about human physiology.

  2.  

    I think this is because the hydrogen and oxygen molecules are "adsorbed" onto the surface of platinum. This changes the bonding energy of the molecules and brings them closer together thus making the reaction easier (more energetically favourable). I'm not sure that the detailed physical processes involved are that well understood. (Well, not by me, anyway!)

    There have been DFT models made of simple diatomics and small molecules being adsorbed onto a metal surface. It has to do with overlap of the molecule's HOMO and the metal's conduction band IIRC.

     

    Other than that I know very little about the topic. Surface chemistry is incredibly incomprehensible to me for some reason. I have no intuition for it and the useful calculations are quite high level.

  3. When I first started undergraduate I gained access to a lot of books and journal literature and realized how much science and math that there was to learn. It still feels like an infinite well of stuff to learn. I argue that it still is. I'll hazard a guess that data and knowledge is generated faster than any one person could learn.

  4. But PF was huge, even back then, and it was easy to get lost in the crowd. I joined SFN and found the smaller community more refreshing and engaging.

     

    I feel like SFN is large enough to offer a wide diversity of knowledge and opinion yet small enough for one to get to know the personalities of the regular posters. I like that the community is close-knit enough to have several running gags like staff cheese nips and organic chemistry innuendos.

     

    It truly is the best of both worlds. There is enough expertise here that an amature or professional (from a different field of study) really does stand to grow their knowledge base by spending time here yet there is still a strong sense of community.

     

    I know I don't post often anymore (work, work, work) but I'm still reading guys. You see that spooky figure in the shadowy corner glaring at you and nodding when you make a good point? That's me.

  5.  

    To be fair, there is not even a prize for biology. We do have to poach what we can, just as in real life (although were there so many biologists? I thought they were biochemists, the bastard children that no one really loves).

    I always thought it strange that there was a prize for medicine and not for biology. Especially when many see physics, chemistry, and biology as "the big three" from which other sciences are derived.

  6. In terms of heat capacity? Thermal conductivity? How much energy can be absorbed before ionization?

     

    As worded the question is too vague. Help us understand your question better.

  7. It seems more like a free-for-all in physics because it's less immediately tangible or tactile than other subjects so the potential scope for arm-waving is greater.

    Agreed. Coupled with the fact that many questions in chemistry and presumably biology (no experience here), are easily testable.

     

    Crackpot: Can I make this chemical with these chemicals?

     

    Chemist: No

     

    It's much easier to be dodgy and intellectually dishonest with one's self and others on topics such as dark matter, bad physicsy-philosophy, string theory and such. Add in a total non-understanding of anything even related to physics or math and a crackpot is born.

  8. What are Quantum Dots and how we can use it/imply it in Electrical and Electronic systems

    What is your level of understanding? Are you a student or do you have any background in chemistry or physics?

  9. OP,

     

    As Klaynos pointed out, not being able to answer questions about theory or equipment DOES matter. Would you hire a carpenter who didn't know how to use a saw? Or didn't know pine from cedar?

     

    What are your strengths? If you are not a strong spectroscopist you shouldn't be applying for analytical work. Not everyone is well suited for every job. For example, I would feel right at home in front of an infrared spectrometer in a materials lab but would probably be fired as an idiot trying to do enzyme target screening in a drug discovery lab.

     

    If you tell me what you know, maybe myself and other working chemists here can direct you accordingly.

  10. Medical Lab tec and similar are far from the lowest jobs for science graduates. Many engineering and science graduate have to take jobs outside their field and many end up in menial jobs. I will say that this is in the UK, maybe the US looks after its graduates better.

    The situation is no better across the pond. I've had a science degree for several years (high GPA, several papers, good lab experience) and have just recently obtained a job in my field. Jobs are there, but it seems like qualified people are having to fight to get them. Luckily I was able to find a decent non-science job to feed myself between graduation and now.

     

    This is of course anecdotal and the stats may prove me wrong. I do know many others who were in the same situation though.

  11. An annoying technical note that may or may not be helpful to the OP:

     

    Strictly speaking, in order to be considered fluorescence the decay must be from the first singlet excited state to the ground state. If intersystem crossing occurs then we are talking about phosphorescence instead of fluorescence.

     

    Jablonski diagrams may be a helpful tool in understanding the difference between all the different types of molecular electronic decays.

  12. The claim is a bold one for sure. The chemistry blogosphere is full of cheers and jeers because the possibility of these types of covalent interactions (where a large portion of the electron density is contributed from non-valence atomic orbitals) has been a contentious issue for some time now.

     

    I have my reservations about how anyone plans to test this. The conditions under which these compounds would form DO NOT lend themselves to clean, irrefutable spectroscopic analysis.

     

    My bet would be that someone tries to observe these chemical abominations with some sophisticated calorimetry or other thermo-analytical method.

     

    I highly anticipate the first attempts at real life observation of these compounds both for the chemistry itself and what it might say about high level quantum chemical computation as a predictive tool in general.

     

    I've been following the literature closely on this issue and will continue to. Thanks for sharing it with SFN, and touche for beating me to it.

  13. I'm going to second John's answer. I think short wave UV (or arguably NMR depending on the instrument's field strength) would be the most accurate method. However, the UV route may be problematic depending on what other species are in your sample.

     

    I do not recommend IR spectroscopy for a number of reasons. I'll be glad to tell you why if you are curious.

     

    A density measurement would give you a quick check with reasonable accuracy.

     

    This all depends on your access to equipment and precision requirements though.

  14. That's true but the 'chance' parts are the necessary molecules being in proximity to each other and under conditions that allow them to react.

    That is strictly true. However, it's important not to forget that we must average over a large ensemble of reactant molecules.

     

    Let's say that the probability of any A molecule reacting with a B molecule to give a C molecule is very small.

     

    If the formation of C is thermodynamically favorable and the reverse reaction of C reverting to A+B is sufficiently slow, then there can be a net build up of C over time. Thermodynamics trumps kinetics in the limit of relatively long time scales.

     

    I agree with your post but felt I should add that tidbit. Carry on :)

  15. Well, kinetic and thermodynamic isotope effects are in general small. The most noticeable effect is when we exchange protium for deuterium as deuterium is essentially twice as heavy as protium. The small difference is easily observed by comparing sensitive enough IR spectra of HCl and DCl. This means that the energy of the bond changes when you switch isotopes.

     

    Treating the vibration of a chemical bond as a quantum harmonic oscillator we find that the isotope effect for pairs of isotopes in other elements is much smaller as the reduced mass (a constant in the Schroedinger equation for the QHO) of the system changes relatively little with the addition of a neutron to a heavier element.

     

    This also holds for more rigorous treatments of the chemical bond that don't use the reduced mass approximation.

     

    Physical properties such as boiling point are affected but also to a small degree in most cases.

  16. Can anyone else confirm or deny what mr Cuthber just said?

     

    Seems pretty arrogant for a tv show to show us something that is out of the realm of possibilities.

     

    Do molecules have a frequency that can be measured?

    I'll confirm.

     

    There are ways of using light to determine an unknown substance. See spectroscopy.

     

    What you have seen on said TV show does not exist.

  17. If you have any interest in density functional theory, DFT (which you should), then take a functional analysis course. You could get by without it but you will be a cut above the rest if you choose to take it.

     

    I would also encourage a good PDE course. Do you have any interest in relativistic quantum chemistry?

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.