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studentgary

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    studentgary reacted to exchemist in The Temperature In Space   
    Well not 3F, but 3K. If you were shaded from any nearby stars.
     
    3K means 3 degrees Celsius above absolute zero, which is the temperature at which there is no heat energy left in a body. So 3C above that is -270C, or -454F. 
     
    Space itself, being a vacuum and not made of matter, can't really be said to have a true temperature in the strict sense. But the cosmic background radiation that pervades space is the same as the heat radiation from a body at about 3K. So if a piece of matter (a piece of rock for example) were exposed only to that radiation, that is the temperature it would end up at, once it had reached thermal equilibrium with the radiation. 
     
    If it were not for the big bang, one would not expect there to be any such radiation. So people in the past would have expected that a shaded body in space would radiate heat away until its temperature had dropped to absolute zero itself. The fact that there is this radiation rattling around the universe and apparently coming from everywhere, not from any identifiable source, is a key piece of evidence for the big bang hypothesis.
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    studentgary reacted to exchemist in Trump   
    This feeling will get even worse if Oprah Winfrey becomes the next Democrat president! Let's hope all that was just showbiz people demonstrating their usual self-absorption and hysteria. But then.... Trump is a showbiz person.........Yikes!
  3. Like
    studentgary reacted to Mercedes Benzene in Chemistry 101   
    You can't say that an acid or base is stronger.
    They are completely different things!
     
    The pH scale is a measure of the Hydrogen ion concentration in a given substance.
    The pH scale ranges from 1 to 14.
    The number 7 is neutral.
    As the number increases past 7, the substance in more basic (or alkaline).
    As the number decreases below 7, the substance is more acidic.
    a pH of 1 would be extremely acidic.
    a pH of 14 would be extremely basic.
     
    now pH is simply the negative logarithm of whatever the concentration may be.
     
    For instance, lets say a substance has a hydrogen ion concentration of .08
    The pH can be determined thusly:
    -log10(.08) = ~1.09
    This would be a very strong acid.
     
    On the other hand, if the ion concentration was 1.06x10^-13, when plugged into the equation:
    -log10(1.06x10^-13) = ~12.97
    That would be a fairly strong base.
  4. Like
    studentgary reacted to UncleAl in Chemistry 101   
    Not nearly good enough. You must know everything to know anything. Rote memorization leaves you an educated cripple - a biologist's head bursting with vast numbers of disconnected facts. You must understand.
     
    Is your left foot different from your right foot even though it is a mirror image? Sure! A given shoe wll fit differently on either foot. How different is your left foot from my left foot? How do you quantitate footedness? One is knowledge, one is understanding. Uncle Al needed 18 months of daily work to understand said mathematics. His first hint of success was finding an (admittedly small) error in the mathematician's published work. Number Two was causing NIST's commercial stereochemistry software to be rewritten. It had passed tens of thousands of test cases. So? Theory is killed by a single contradiction.
     
    There is reason to believe the whole of physics is wrong for the same reason. Predictions will not change but theory must be completely rewritten - with new options appearing. Nobody will do either of the probe experiments because "they cannot possibly work." But they can, and without raising a sweat while succeeding. Somebody should look.
  5. Like
    studentgary reacted to hazelm in Cell Phone Vs Telephone   
    The state of California has warned its citizens that cell phones are indeed dangerous to one's health.  So, somebody please tell me.  What is in cell phones that is not in Alexander's telephones?
     
    I was going to say that among the dangers (like brain cancer), they didn't list the one thing I truly think is a danger: addiction and its negative social results.  But then I remembered the 50s and 60s teens tying up phones for hours.
     
    Anyway, back to my question.  What is in cell phones that is not in Mr. Bell's invention?
  6. Like
    studentgary reacted to exchemist in Diesel Fuel   
    I suspect your friend may be confusing water with hydrogen!
     
    Hydrodesulphurisation is the method generally used to reduce sulphur in hydrocarbons. It relies on adding hydrogen, which, with the action of a suitable catalyst, takes sulphur out of the fuel, turning it to hydrogen sulphide, which can be further reacted to produce elemental sulphur or sulphuric acid, which has industrial applications. More here: https://en.wikipedia.org/wiki/Hydrodesulfurization
     
    I think you friend saw "hydro" and thought "water". Understandable, but not correct.   :)
     
    On the exhaust treatment side, I was surprised you are adding urea. That implies SCR, selective catalytic reduction: https://en.wikipedia.org/wiki/Selective_catalytic_reduction  which I had understood was more commonly used on large diesels in power gen and marine. For most automotive diesels I had thought this was too cumbersome. But your question has prompted me to look this up and indeed it seems that from 2010 in the US SCR became one route to achieving the new standards that came into force at that time.  I think in Europe the method was to reduce peak combustion temperatures so that less NOx was formed and also to use EGR (exhaust gas recirculation) to reduce the amount of free oxygen available in the cylinders to convert nitrogen to NOx.
     
    But these technologies are evolving all the time. The regulatory authorities in the US and Europe often follow different routes and play leapfrog, which is probably a good thing for the planet as it forces the exploration of a variety of technical routes.
  7. Like
    studentgary reacted to Buffy in Best Arguments Against Christianity   
    Don't stop Hazel, there's lots to discuss.
     
    My thesis since childhood is that churches from time immemorial have been simply a means of enforcing the legitimacy of government. To the extent we've separated the two, religion has moved toward simple moral suasion over politics. This reduction of power has bred jealousy,and attempts to increase the influence like the current US administration's new rule allowing explicit political advocacy while retaining their tax exempt status.
     
    Of course the political capture of the Evangelical Christian movement by the conservatives in America in service of libertarian philosophy has created a very strange movement with all sorts of potential cognitive dissonance glossed over by the extremity of pure "faith" in those philosophies.
     
    Thus we end up with Evangelicals being the biggest backers of Roy Moore despite his very un-Christian behavior that disgust virtually everyone else.
     
    And of course look what Jesus did to those money changers, and gosh all that talk about rich people and camels and eye's of needles.
     
    Jesus was a Trotskyite, you know.
     
     
    Even so ye also outwardly appear righteous unto men, but within ye are full of hypocrisy and iniquity, :phones:
    Buffy
  8. Like
    studentgary reacted to hazelm in Best Arguments Against Christianity   
    If I am allowed a comment, this has gone through my mind many a time.  Are we judging "Christianity".  Or are we judging the churches that claimed (and still claim) to be "Christians"?  Is Christianity a political organization that has gone terribly astray?    Or is Christianity a philosophy that never came to be?  If you want to argue against Christianity, is it wrong for me to ask which Christianity? Or, what is Christianity?  Is it the ethics that "mellows people so they live and work together in peace"?  (HydrogenBond)  Or is it the "hell fire and brimstone" shouted from pulpits?  Or, to be historical, the inquisition?
     
    I had better stop.  Please define the Christianity you want to debate.  Or is my question out of order?
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