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by In Wales Sun Dec 13th, 2009 at 10:41:15 AM EST
We went over to Penarth, which I believe has been a filming location and from there you can see Flat Holm Island, another ratehr fabulous location.
Now I get to eat more of yesterday's apple crumble and get started on an essay that I don't want to be doing last minute on Wednesday night like last month... (which despite not having time to put a conclusion in, I got 73% for).
Yes, it's nerd Sunday! They tried to assimilate me. They failed.
My phys chem textbook has been borrowed by a friend but let's see...
By having impurities in the solvent, it alters the energy of the system. Depending on what the impurity is, the electrostatic forces between water-impurity are different to the forces between water-water. Also, by adding an impurity, you've effectively diluted the solvent.
With sea salt, the presence of Na+ and Cl- causes a restructuring of the alignment of water molecules in order to keep the charges dispersed and dissolved in solution. But salt isn't dissolved in the solid state. Therefore the chemical potential of the solvent in the solid state is unchanged. But the chemical potential of the solvent in liquid state is changed.
Chemical potential is to do with the energy of the system. The freezing point occurs when the energy of the solid state is in equilibrium to that of the liquid state and this is temperature dependent. If you change the chemical potential or energy of the system by introducing impurities, you change the point at which that equilibrium between solid and liquid state occurs.
The freezing point drops because the new chemical potential of the impure solvent in liquid state needs to find the new equilibrium point with the solid state solvent, and this is occurs at a lower temperature.
Can you give me a layman's view of what it means? Never got it straight in college/grad school and ain't doing much better now.
Thank You. They tried to assimilate me. They failed.
In this case the claim is that the chemical potential between water ice and pure water is higher than the chemical potential between water ice and water with a solute. The chemical potential depends on the concentration of the solute.
The chemical potential difference between pure water and water with a solute is proportional to the osmotic pressure across a semipermeable membrane separating pure water from water with a solute. En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma
Is that it? They tried to assimilate me. They failed.
If you have to "buy" #2 but you "get" osmotic pressure"...
How do you explain osmotic pressure in layman terms in a way that doesn't make it easy to see that it is proportional to the energy difference per water molecule between two phases with differenc solute concentrations?
The energy per molecule is by definition the chemical potential. En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma
In the wikipedia article on freezing point depression it says
The freezing point depression is a colligative property, which means that it is dependent on the presence of dissolved particles and their number, but not their identity. It is an effect of the dilution of the solvent in the presence of a solute. It is a phenomenon that happens for all solutes in all solutions, even in ideal solutions, and does not depend on any specific solute-solvent interactions. The freezing point depression happens both when the solute is an electrolyte, such as various salts, and a nonelectrolyte. In thermodynamic terms, the origin of the freezing point depression is entropic and is most easily explained in terms of the chemical potential of the solvent.
A related notion, osmotic potential is the opposite of water potential, is the degree to which a solvent tends to stay in a liquid.
the potential energy of water relative to pure free water (e.g. deionized water) in reference conditions. It quantifies the tendency of water to move from one area to another due to osmosis, gravity, mechanical pressure, or matrix effects including surface tension. Water potential is measured in units of pressure and is commonly represented by the Greek letter Ψ (Psi). This concept has proved especially useful in understanding water movement within plants, animals, and soil. Typically, pure water with standard temperature and pressure (or other suitable reference condition) is defined as having a water potential of 0. The addition of solutes to water lowers its potential (makes it more negative), just as the increase in pressure increases its potential (makes it more positive). If possible, water will move from an area of higher water potential to an area that has a lower water potential. One very common example is water that contains a dissolved salt, like sea water or the solution within living cells. These solutions typically have negative water potentials, relative to the pure water reference. If there is no restriction on flow, water molecules will proceed from the locus of pure water to the more negative water potential of the solution.
lowering of vapor pressure; elevation of boiling point; depression of freezing point and osmotic pressure.
Chemical potential energy is a form of potential energy related to the structural arrangement of atoms or molecules. This arrangement may be the result of chemical bonds within a molecule or otherwise. Chemical energy of a chemical substance can be transformed to other forms of energy by a chemical reaction. As an example, when a fuel is burned the chemical energy is converted to heat, same is the case with digestion of food metabolized in a biological organism. Green plants transform solar energy to chemical energy through the process known as photosynthesis, and electrical energy can be converted to chemical energy through electrochemical reactions. The similar term chemical potential is used by chemists to indicate the potential of a substance to undergo a chemical reaction.
Chemical potential energy is a form of potential energy related to the structural arrangement of atoms or molecules. This arrangement may be the result of chemical bonds within a molecule or otherwise. Chemical energy of a chemical substance can be transformed to other forms of energy by a chemical reaction. As an example, when a fuel is burned the chemical energy is converted to heat, same is the case with digestion of food metabolized in a biological organism. Green plants transform solar energy to chemical energy through the process known as photosynthesis, and electrical energy can be converted to chemical energy through electrochemical reactions.
The similar term chemical potential is used by chemists to indicate the potential of a substance to undergo a chemical reaction.
In the most basic layman terms possible when you discuss chemical potential, you are talking about the energy of the components that make up the system.
The chemical potential of a molecule depends on the bonds it forms, how easily these can be broken, what they react with and how much energy is released/absorbed in a reaction etc.
The chemical potential (energy) of the pure component therefore won't be the same as the chemical potential of the component when diluted by an impurity. The equations show how this works.
Have you done free energy calculations? This is essentially a chemical potential calculation.
and don't feel so bad about not getting it: The chemical potential
A vague discomfort at the thought of the chemical potential is still characteristic of a physics education. This intellectual gap is is due to the obscurity of the writings of J. Willard Gibbs who discovered and understood the matter 100 years ago.
Because physicists look down on chemistry, don't learn it well and teach it even less well. I found that chemists (at least physical chemists) have a much better intuitive and quantitative understanding of thermodynamics. Physicists rarely talk about the chemical potential as chemistry is too messy. In addition, Physicists tend to go straight to statistical mechanics thinking that the manipulation of thermodynamic potentials is a trivial matter once you have a partition function, which is not the case. En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma
Not really to nitpick since I am not sure I fully understand it myself, but it appears that chemical potential has to do with colligative properties which
depend on the number of molecules in a given volume of solvent and not on the properties (e.g. size or mass) of the molecules.
There are some articles I came across which made the distinction between chemical potential and the free energy (Gibbs energy) of the system which do get confused and I'm guilty of that.
It is why I asked if the Twank had done free energy calculations because the difference in energy (either absorbed or released) when a reaction takes place is a chemical potential calculation effectively.
In the case of salt in water, in a given volume, the addition of salt which splits into two ions, effectively dilutes the solvent and decreases the chemical potential - the values can be plugged into the right equations to show the effect that has in reducing freezing point etc.
Gibbs Free Energy and Pressure, Chemical Potential, Fugacity
Gibbs free energy per mole of substance ... This quantity is called the chemical potential and it is given the symbol, μ
Chemical potentials
In an aqueous solution of salt or of another solute, the chemical potential of water is lower than the chemical potential of pure water. The chemical potentials of pure ice and pure water vapor however, are independent of the composition of the solution from which it was formed. At equilibrium water will be in the state that has the lowest chemical potential. Therefore an aqueous solution has a lower freezing point and a higher boiling point (lower vapor pressure) than pure water.
But in terms of trying to find an explanation that can help to visualise how that happens I always look at how the molecules interact because it helps me to find some logic to help the concepts stick.
The Gibbs Free Energy does not incorporate quantities of matter or chemical potential. Gibbs realised that when the quantity of matter can change, you need an additional energy term proportional to the quantity of matter and you define chemical potential as, (for instance) the Gibbs Free Energy per mole of substance at constant temperature and pressure. Of course, adding matter to a system at constant temperature and pressure requires increasing the volume of the system, but that's okay... En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma
Thank you for the help on the P. Chem.
Later! They tried to assimilate me. They failed.
It's just cos I've still got this fag-end of a cold, so I'm kinda sensitive to this. I'll be feeling nostalgic this time next year when the temperature is in the mid-teens. This is gonna be the last cold winter for some time. keep to the Fen Causeway
This is gonna be the last cold winter for some time.
That a joke? You know something I should? They tried to assimilate me. They failed.
Bear in mind I'm not a climate scientist and that there are a lot of mitigating bits of information I don't know. that said my understanding is as follows;- We've had the elNina for 2 - 3 years which has been keeping us cold coupled with the solar minimum which has been compounding that cooling. They have tended to obscure the general warming trend which means that, although this decade was warmer than last decade, this hasn't fed through in europe.
now that both of those phenomena are ending the gloves are off temperature wise. Next summer is gonna be hot, next winter won't be that cold and the summer after will be hotter etc etc.
this goes on for 6 - 7 years. If the methane in Siberia doesn't go we've got another 7 years after that. However in 12-13 years time we're back in the same place, just at a warmer starting point. Sooner or later the methane will go and we won't get back to Kansas in our lifetime.
And nothing our weaselling corporate sucking politicians decide in copenhagen is gonna be anything like enough. keep to the Fen Causeway
Nobody ever mentions the methane hydrate at the bottom of the ocean. Doesn't it matter? They tried to assimilate me. They failed.
Why? Because it's not a linear system. The connection between Climate and Weather is like the difference between the sidelines of a football - your football - pitch and the play. You can predict the play will occur within the pitch but the exact course of play and where the ball will be at any point during play is unpredictable. She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre
Oceans simply don't warm up that quickly. keep to the Fen Causeway
So hey - not to worry! The fact is that what we're experiencing right now is a top-down disaster. -Paul Krugman
European Tribune - Climate Science: Got Doom Today? (Part 2)
it shows that with an increasing temperature there is an increasing amount of CH4 in the atmosphere. But in one case the D/H deviation does not change at all, or in the posted graph, it lags behind the CH4 increase and when it does change, the deviation decreases. In a final devastating blow to the clathrate gun, Sowers made a model that simulated what would happen if all the CH4 released in the atmosphere would be from the clathrates with a -189 per mil D/H signature. This gives the black line in the graph and shows that the simulation resulted in an increase (less negative) of the D/H deviation, the precise opposite of what the record is showing. In one stroke, Sowers delivers damning evidence that the clathrate gun hypothesis in the earth's most recent history is not even smoking. In fact, it provides the question whether it was loaded in the first place. And this is good news, since it indicates that the methane stored in the oceans is a LOT more stable than what many people were speculating. It shows that even with abrupt warming events in our recent history, the clathrates contribute insignificantly to increasing global CH4 concentrations.
it shows that with an increasing temperature there is an increasing amount of CH4 in the atmosphere. But in one case the D/H deviation does not change at all, or in the posted graph, it lags behind the CH4 increase and when it does change, the deviation decreases. In a final devastating blow to the clathrate gun, Sowers made a model that simulated what would happen if all the CH4 released in the atmosphere would be from the clathrates with a -189 per mil D/H signature. This gives the black line in the graph and shows that the simulation resulted in an increase (less negative) of the D/H deviation, the precise opposite of what the record is showing.
In one stroke, Sowers delivers damning evidence that the clathrate gun hypothesis in the earth's most recent history is not even smoking. In fact, it provides the question whether it was loaded in the first place. And this is good news, since it indicates that the methane stored in the oceans is a LOT more stable than what many people were speculating. It shows that even with abrupt warming events in our recent history, the clathrates contribute insignificantly to increasing global CH4 concentrations.
I note that I didn't get around to bring back the pictures back on-line. Will be done... This discussion on methane clathrates is like a bad zombie movie.
There's also a relationship between temperature and pressure -- which I don't understand.
Near as I can tell, based on my minimal understanding, by the time the deep-ocean methane would be released the affects and effects of conditions required for it to be released would have effectively destroyed the world As We Know It anyway. She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre
I don't think this is incoherent so much as showing how different parts of the electorate are going in different directions. I suspect the working classes are trending right and the middle classes are recoiling from the tories.
Quite how this plays out I don't know cos it's a long time till polling day. Although Brown can hang on till May, people are now suggesting that mid-March is possible.
Can I say that I want them both to lose. I have learned to hate NuLab with a passion and cannot vote for them while that faction still dominates. I wanted a Labour government in 1997 and got a bunch of tories who cacked the country up and I have finally tired of voting for them in the hope of anything better. I will not endorse this catastrophic neoconservative government.
Yet much more than NuLab, I despise the conservatives. Part of my anger with NuLab is that they've taken away the obvious protest vote against the tories. Cameron and Osborne will ruin the country by greenspanning us to death. their plan of attack on the deficit will be a bonfire of services to the poor and even medium well off. Wealth capture will be accelerated as the country will be tipped upside down to ferret out the very last bit of worth for the wealthy to clutch.
but who will win ?
I'd love to be able to say I don't care; but I do. It matters. I'm reckoning on a hung parliament. I think Labour will lose loads of seats but not enough for Cameron the terrible to form a government that cannot be voted down. Largely because the Lib Dems will be utterly routed and Labour will pick up those seats preferentially.
But watch Scotland. The political landscape for the next two or three decades will be decided there. If the tories win outright, scotland will vote for greater independence and that means that, under the first past the post electoral system, conservatives will rule england forever.
If it's a hung parliament, Scotland will stay in the UK and nothing will be settled. keep to the Fen Causeway
Helen:
the reslut
It's depressingly apt.
Drugs money worth billions of dollars kept the financial system afloat at the height of the global crisis, the United Nations' drugs and crime tsar has told the Observer. Antonio Maria Costa, head of the UN Office on Drugs and Crime, said he has seen evidence that the proceeds of organised crime were "the only liquid investment capital" available to some banks on the brink of collapse last year. He said that a majority of the $352bn (£216bn) of drugs profits was absorbed into the economic system as a result.
Antonio Maria Costa, head of the UN Office on Drugs and Crime, said he has seen evidence that the proceeds of organised crime were "the only liquid investment capital" available to some banks on the brink of collapse last year. He said that a majority of the $352bn (£216bn) of drugs profits was absorbed into the economic system as a result.
It certainly seems to be working... The fact is that what we're experiencing right now is a top-down disaster. -Paul Krugman
Yesterday, I saw Ronnie O'Sullivan's absolutely amazing comeback from 2:8 to 8:8 (in a game played until 9 wins), only to end in a 9:8 for Higgins after O'Sullivan gave up just one snoker down (why?). If Higgins survived that onslaught, I wonder if Ding has a chance at all. *Lunatic*, n. One whose delusions are out of fashion.
...is that the game that (seemed to me, anyway) an odd cross between billiards and pin-ball? "Beware of the man who does not talk, and the dog that does not bark." Cheyenne
A very relieved Higgins told BBC Sport: "There is nothing more frightening than Ronnie coming back at you when he's in full flow. "I was just sitting there and thinking if I get a chance take it. You can't take liberties with Ronnie. "At 8-2 in front you might think that against anybody else."
A very relieved Higgins told BBC Sport: "There is nothing more frightening than Ronnie coming back at you when he's in full flow.
"I was just sitting there and thinking if I get a chance take it. You can't take liberties with Ronnie.
"At 8-2 in front you might think that against anybody else."
Yes indeed... *Lunatic*, n. One whose delusions are out of fashion.
Meanwhile, I see Ding-Higgins ended the afternoon session 4:4 -- it could be a long night. *Lunatic*, n. One whose delusions are out of fashion.
The incident has been unanimously condemned although De Pietro also called attention to the obvious: Berlusconi is exasperating the situation at all costs. In the end this act of violence is exactly what Berlusconi wants. He will exploit it to the hilt.
Since then, wherever the little Silvio goes this word is sure to go.
Actually, Berlusconi visited Lukachenko recently- hailed him as a great democrat, loved by his people- and received four dossiers on Italy and the Eastern bloc. Three dossiers deal with WWII. The last dossier smells surprisingly similar to the farragoes produced by the Mitrokhin commission alleging that the Italian Communist Party colluded with the communist satellite states to foster terrorism in Italy. I suppose he asked Luk if he could slip in a fourth dossier...
We are being browbeaten by the media about our supposed crimes for months now.
Berlusconi will pull out these dossiers under elections just as he did in 2006. Same tired script.
PS. The robes are red for all the blood judges have sacrificed in the name of the law.
Any hope this tactic is not so effective with younger voters? She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre
BBC News - Italy's PM Silvio Berlusconi is bloodied by attack
Prime Minister Silvio Berlusconi of Italy is recovering in hospital after an assault left his face covered in blood following a rally in Milan.He suffered two broken teeth, a minor nose fracture and cuts to his lip after being struck by a man wielding a souvenir model of the city's cathedral.
Prime Minister Silvio Berlusconi of Italy is recovering in hospital after an assault left his face covered in blood following a rally in Milan.
He suffered two broken teeth, a minor nose fracture and cuts to his lip after being struck by a man wielding a souvenir model of the city's cathedral.
Schell was the incumbent yet lost in the first round of the election. I always saw a connection between the two. When the citizenry are attacking you in public it's hard to be seen as a legitimate leader.
Now, there was a major who is also MP who first making headlines with an evidence-free claim that local Roma women beat their unborn children with hammers to make them imbeciles eligible for social supports; then envisioned Jewish capital that wants to take over Hungary. This was a bit too much for the party leadership, who deselected him as candidate in nexrt years' elections. Against the unanimous endorsement of the local Fidesz branch...
So how to please the idiots? They aparently chose to parachute a Lebanon-born Palestinian as candidate for the region. I leave it to you to figure out the message behind the choice... *Lunatic*, n. One whose delusions are out of fashion.
Still, I guess it's one way to make an impact... The fact is that what we're experiencing right now is a top-down disaster. -Paul Krugman
I'm confident in his ability to run anti-freeze through his arteries and veins cope. She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre
tomorrow an 8 hour trucktrek to san jose, overnight near the airport, then tuesday afternoon i enter into the space-compression tube, aka airplane for the 12 hour squeeze to madrid, where i will be extruded onto euro soil again.
then 2 hrs later the last leg to rome, then a 3 hr bus ride to perugia, then my friends pick me up and take me home again...
very mixed feelings assail me this last evening, meditating on the manifold blessings and challenges this trip has afforded, and the spirit i hope to maintain alive once returned to the lands of my forefathers, the olde worlde of my roots, to puzzle more on the different takes on the human condition due to geography and adaptation.
most of all i'll miss the spontaneous kindness of the 'ticos', (affectionate term for costa ricans), and the wondrous energy of the ocean, as it slams and caresses the pacific coast.
bodysurfing was appropriately amazing on the last swimming day, tide was high and the foam boiling like a giant jacuzzi.
when the waves came at me they looked like 10,000 white horses galloping, some glorious rides right into 2 inches of water, bout sanded my forehead off one time...
there's a big bonfire on the beach tonight, better go check it out.
europe seems like a distant, senile circus from here and now, i wonder what it's going to welcome me back with!
winter, with its long bloggy nights, hearing the winds howl over the hilltop, chopping wood, saunas and hot springs, mucho music, new tunes to commit to disc, banging on the pianner again.
not too bad...
a toast to the fine tico hospitality, and all the interesting characters i swapped stories with these last two months!
lotsa pix too, but i have to do a lot of flickr-ing first.
pura vida
m 'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty
Or vice versa.
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