Study of macroscopic and microscopic phenomena in chemical systems in terms of physical laws and concepts [thermodynamics, statistical mechanics, kinetic theory, quantum mechanics...].
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0answers
44 views
If air contains oxygen and nitrogen, why won't these two elements form water? [closed]
If air contains oxygen and nitrogen, why won't these two elements form water?
Shouldn't these two elements react and form water? Why do they stay seperated?
1
vote
0answers
19 views
Solution of multiple materials
Introduction
I'm trying to make some strawberry liqueur. The recipe I got says I should put alcohol, strawberries and sugar in a bowl and leave it soaking for 4-5 weeks. I read that making liqueur is ...
2
votes
3answers
982 views
Widom-Larsen Theory
Does the Widom-Larsen theory pose a credible underpinning for Low Energy Nuclear Reactions, often incorrectly referred to as "Cold Fusion"?
http://arxiv.org/abs/cond-mat/0505026
-2
votes
2answers
45 views
what is the density of natural gas at 293K and 700 kPa? [closed]
I am trying to calculate the density of natural gas to define the amount of natural gas flow through an orifice. I am coming up with 5.45 kg/m3 Is this correct?
2
votes
3answers
645 views
is it possible to flow current in open circuit?
First , i don't know much about chemistry and physics. I'm just a graphic designer but i have this question in my mind. I'm sorry if this question is too basic and use 'generic' language.
As i know ...
0
votes
2answers
29 views
A question on lewis model
Electron affinity of chlorine = -349 kJ per mole. And, first ionization energy of sodium = 496 kJ per mole while energy required for combining= 147 kJ per mole.
Isn't it a contradiction against ...
0
votes
1answer
47 views
What is tricritical point？
Critical point is the transition temperature of a second order phase transition. But what does tricritical point mean? WIki says that a tricritical point is a point in the phase diagram of a system at ...
-3
votes
0answers
36 views
effect of gravity on chemical reaction rates [closed]
a chemical reaction is done on earth in very vacuum and that chemical reaction is also done in space so that gravity higgs field not affect that reaction.
Which reaction will be fast wrt gravity and ...
1
vote
1answer
63 views
How fair is it to say that all chemistry arises from failures of the ideal gas law?
I was reading here about how the ideal gas law assumes point masses and non-interaction. Is it fair to say that all chemistry arises from failures of that?
Of course, such a sweeping generalization ...
0
votes
2answers
79 views
Carbon in the form of graphite a conductor?
Well, it happens a I have a glucose test strip (One Touch Ultra) which has three electrodes (Counter, Working and Reference) and I'm guessing this electrodes are made from graphite mixed with a ...
6
votes
1answer
87 views
How much Bicarbonate of Soda and Vinegar would I need to reach space?
So here is my problem - as part of my job I present some science demonstrations to children and one of the tricks I regularly use is the bicarb/acetic acid rocket. I thought the other day that a ...
-4
votes
1answer
86 views
How fast will I get if I burn a comet? [closed]
Assuming I have a spacecraft which is $30,000\,\mathrm{kg}$ (roughly the size of the Apollo spacecraft).
If I take a comet and (theoretically) electrolize it perfectly to hydrogen and oxygen. I know ...
5
votes
2answers
105 views
Solidification by the application of heat
When you add heat to a liquid (or a fluid), can it be solidified? If not, why in the world does an egg's stuffs become solid (or at least no more a liquid) when you 'boil' it in water?
3
votes
2answers
172 views
When do thermal and chemical equilibrium not coincide?
What is an example for a system, which is in chemical equilibrium, but not in thermodynamical equilibrium?
And what about the other way around?
It seems to me, that as long as Parameters like ...
4
votes
2answers
202 views
Why are the lighter halogens gases?
In the periodic table of the elements, only a few of the elements are gases at standard temperature and pressure. Those elements include the noble gases some of the halogens, and a few of the elements ...
12
votes
6answers
1k views
Where should a physicist go to learn chemistry?
I took an introductory chemistry course long ago, but the rules seemed arbitrary, and I've forgotten most of what I learned. Now that I have an undergraduate education in physics, I should be able to ...
0
votes
2answers
49 views
What is “species” in the context of an electrochemical cell?
From the Wikipedia entry on Electrochemical cell (http://en.wikipedia.org/wiki/Electrochemical_cell):
An electrochemical cell consists of two half-cells. Each half-cell
consists of an electrode, ...
0
votes
1answer
88 views
Difference between Non-Polar and Dipole moment $\vec\mu$=0
Is there any difference between a molecule having $\vec\mu=0$ and being Non-Polar?
14
votes
3answers
477 views
Why the distribution of elements on earth?
I've been wondering exactly why the elements are distributed the way they are on earth. The heavier elements have their origins in the centers of stars, or in supernova. After the death of the stars, ...
6
votes
2answers
1k views
Why is quicksilver (mercury) liquid at room temperature?
This is a nice question when you find it out, and I am really looking for a proper answer.
Take quicksilver (Hg) in the periodic table. It has one proton more than Gold (melting point 1337.33 K), and ...
1
vote
1answer
2k views
List of immiscible liquids
I'm looking for a list of immiscible (and miscible) liquids.
I currently developing a game that will use the property of differents liquid, some of them will mix, other will not (positioning in the ...
17
votes
3answers
5k views
Why does the water rise?
It's a very popular experiment (eg), from elementary school : put a burning candle on a dish filled with water, cover the candle with an inverted glass: after a little while, the candle flame goes ...
2
votes
1answer
43 views
Reason behind cohesive and adhesive force
What is the real cause behind the cohesive and adhesive forces?
1
vote
0answers
59 views
What's the underlying particle physics of endothermic reactions?
I don't just mean reactions that require heat to proceed, storing surplus energy in chemical bonds. I wonder about strongly endothermic reactions that suck heat out of environment.
You take some ...
0
votes
1answer
93 views
Chemical Equilibrium - Why do changes in pressure cause a shift in the ratio of products and reactants?
I understand Le Chatelier's principle and how every change to an equilibrium system causes an opposing reaction from the system. I also understand how, when pressure is increased, the equilibrium ...
0
votes
2answers
3k views
Do salt lamps really produce negative ions?
Do salt lamps really produce negative ions? Do you know about any scientific study that could support this assertion or disprove it?
0
votes
1answer
83 views
What's the vapor pressure and evaporation enthalpy of a saline solution?
Suppose you dissolve an amount of salt in water. Because of the attraction between the ions and the water molecules, you'd expect lower vapor pressure and higher enthalpie, both depending on the ...
6
votes
2answers
1k views
Why does a salt solution conduct electrical current?
How does e.g. sodium chloride (aq) conduct electricity? By accepting electrons (unlikely since they already have a full outer shell)? But they can't be hopping around themselves, can they? I mean, if ...
0
votes
2answers
233 views
What's up in this SPAWAR video?
Here is a video presentation of infrared recordings of anomalous heating in a deuterium palladium cell: ( youtube video) (see also this presentation if you want more detail, and have time). There are ...
4
votes
3answers
140 views
Do electrons in multi-electron atoms really have definite angular momenta?
Since the mutual repulsion term between electrons orbiting the same nucleus does not commute with either electron's angular momentum operator (but only with their sum), I'd assume that the electrons ...
3
votes
3answers
2k views
Why is the energy density of gasoline so high?
We sometimes play a game in my family whereby we trace the energy for a device back to it's source:
The Xbox got power from the wall.
The wall got power from the local transformer.
The transformer ...
1
vote
3answers
128 views
Can endergonic reactions occur outside of living organisms?
If the Gibbs free energy equation is defined as:
∆G = ∆H - T∆S
And the amount of energy/work released from a reaction is:
...
6
votes
2answers
275 views
Statistical Mechanics treatment of the reaction process?
I'm searching for an at least semi-rigorous Statistical Mechanics description/treatment of a (spatially resolved) chemical reaction process of a macroscopic portion of at least two different species ...
1
vote
0answers
28 views
Half-Life Question [duplicate]
Possible Duplicate:
How do we know that some radioactive materials have a half life of millions or even billions of years?
I understand how to calculate decay, but it seems to me that the ...
5
votes
1answer
166 views
What equation describes the electrostatic potential in these circumstances?
I have a solver for Poisson's equation and it works nicely. It uses finite differences. It works in the presence of multiple dielectrics.
It also solves the Poisson Boltzmann equation. That is, fixed ...
0
votes
0answers
318 views
Is there any reproducible tested evidence for Ni-H cold fusion?
The main replications of cold fusion, the ones that are beyond reproach, used Pd/d as the system. But commercial developers have often claim to use Ni-H to achieve similar effects. The claims include ...
1
vote
0answers
63 views
Are metal modes mixed with molecular modes during surface enhanced Raman effect?
This question is dedicated to Martin Fleischmann (1927-2012).
When a molecule is adsorbed on a metal surface, the Raman scattering amplitude from the molecule is enhanced. According to Wikipedia, the ...
1
vote
2answers
153 views
Where does Computer Science background students fit in Theoretical Physics [closed]
I am basically an Electronics student - background in computer science (that's where I want to work). I applied for an internship in USA in a research institute where the group is focused in ...
1
vote
2answers
75 views
Atomic layer deposition applications?
What unexplored areas (known unknowns) are there in atomic layer deposition (ALD)? What unexplored applications of ALD are there? It seems like people use it a lot for coatings of either insulators or ...
1
vote
0answers
38 views
Why the dangling bonds at the edge terminated by hydrogen atoms give no contribution to the electronic states near the Fermi level
How about changing H atom to other kinds of atoms?
3
votes
1answer
383 views
How does a stronger magnet affect the MRI image quality?
In which ways is a stronger magnet better for magnetic resonance imaging? I read that:
The field strength of the magnet will influence the quality of the MR image regarding chemical shift ...
0
votes
2answers
241 views
How does one calculate the volume of a nucleus and the volume of an atom (in this case hydrogen)?
The hydrogen atom contains 1 proton and 1 electron. The radius of the proton is approximately 1.0 fm (femtometers), and the radius of the hydrogen atom is approximately 53 pm (picometers).
0
votes
0answers
18 views
What exponential time dependiciens depends also on temperature?
Are there any laws in nature, which shows exponential decay (or growth) and which also depends on temperature?
For example, don't any chemical transformations demonstrate exponential law? I think ...
0
votes
1answer
49 views
Action on Lard Oil
If water is mixed with lard oil and heated (creating some super-critical liquid with water), how does this affect the volatility of the mixture in comparison with its purity..?
So, My question is: ...
1
vote
0answers
62 views
Chemical reaction as state transition?
When considering diffusion of chemicals, the reaction part is business of chemical kinetics, where the relevant characteristics of different substances come from collision theory together with some ...
1
vote
1answer
80 views
What's the common consensus on the meaning of “physical change”?
I'm doing a textbook problem that shows a "molecular level" view of some matter, little colored balls, before and after, and there are, among the four questions, two that say: 1) Did a physical change ...
14
votes
4answers
1k views
Boiling water and salt
I would like to have a good understanding of what is happening when you add salt to boiling water.
My understanding is that the boiling point will be higher, thus lengthening the process (obtaining ...
11
votes
2answers
2k views
Why do grapes in a microwave produce plasma?
Some of you may know this experience (Grape + Microwave = Plasma video link):
take a grape that you almost split in two parts, letting just a tiny piece of skin making a link between each half-part.
...
0
votes
1answer
98 views
Electrical Resistance and chemistry
Can some one describe or explain what happens when too much current is passed through lets say a copper wire, I am looking for an explanation to do with physics and chemistry.
For instance we have ...
2
votes
2answers
75 views
Driving a solution of optical isomer molecules with the resonant frequency
What happens when we drive a solution of optical isomer molecules (enantiomers) with a microwave radiation in resonance with the tunneling frequency of the molecules (the frequency of the transition ...
