What is mathematics in chemistry

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Beaconator

Beaconator

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I mean I understand balancing an equation, but what does heat pressure and the other variables equate to before durring and after a reaction?
 
Like a min or max before each element ceased to hold its container?

like a pvnrt that couldn’t be held in glass even as a solution.
 
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Ipso defagoi the highest temp any group of elements could “sustain” is the same as the center of the earth
 
Beaconator said:
I mean I understand balancing an equation, but what does heat pressure and the other variables equate to before durring and after a reaction?
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Pressure in gas reactions fulfils the same function as concentration in reactions in solution. So for example, equilibrium constants, usually given the symbol K, can be expressed in either. For example, with a reaction A +B <-> C + D, the equilibrium constant is K = [C].[D]/[A].[ B ] , where [N] is the concentration or pressure of the product or reactant in question.

(If, instead of one mole of a species in a balanced reaction, you have n moles, then you raise the concentration to the nth power. So for example so 2A+B would imply [A]². [ B ] in the denominator.)

The free energy change of the reaction is related to the equilibrium constant by ΔG = -RTlnK = ΔH -TΔS.

H is enthalpy, the sum of internal energy and PV work done on the atmosphere during the reaction, since most chemical reactions take place exposed to the atmosphere, i.e. H=U +PV.

S is entropy, and T is absolute temperature.

So there is your linkage between pressure, or concentration, of reactants and products with energy, entropy and temperature.

There is another family of relationships between pressure or concentration, activation energy, temperature and rate of reaction, but that's another story (Arrhenius equation etc).
 
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exchemist said:
Pressure in gas reactions fulfils the same function as concentration in reactions in solution. So for example, equilibrium constants, usually given the symbol K, can be expressed in either. For example, with a reaction A +B <-> C + D, the equilibrium constant is K = [C].[D]/[A].[ B ] , where [N] is the concentration or pressure of the product or reactant in question.

(If, instead of one mole of a species in a balanced reaction, you have n moles, then you raise the concentration to the nth power. So for example so 2A+B would imply [A]². [ B ] in the denominator.)

The free energy change of the reaction is related to the equilibrium constant by ΔG = -RTlnK = ΔH -TΔS.

H is enthalpy, the sum of internal energy and PV work done on the atmosphere during the reaction, since most chemical reactions take place exposed to the atmosphere, i.e. H=U +PV.

S is entropy, and T is absolute temperature.

So there is your linkage between pressure, or concentration, of reactants and products with energy, entropy and temperature.

There is another family of relationships between pressure or concentration, activation energy, temperature and rate of reaction, but that's another story (Arrhenius equation etc).
Click to expand...
Equations don’t really andwer my questions... real world examples might. Or more specifically those equations don’t answer my questions...
 
Beaconator said:
Equations don’t really andwer my questions... real world examples might. Or more specifically those equations don’t answer my questions...
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I'm not surprised, considering you are as mad as a box of frogs.;) I really only replied in case other readers might expect some kind of an informed response.

But I can have a go at finding you an example, if you can manage to phrase a question in an understandable way. Though it's been many years since I last did these calculations and I don't have a copy of the Rubber Book at home, with all the necessary enthalpies and entropies of formation, so I'd have to try to find the numbers on the internet.

But, whether this thread goes anywhere or not, it belongs in Chemistry, not Physics'n'Maths. I'll ask if James wants to move it.
 
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Beaconator said:
Is there an ambient temperature for every element
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That makes no sense. If a sample of all the elements were placed in room, then all the elements would be at room temperature or in other words at ambient temperature.
Beaconator said:
Like a min or max before each element ceased to hold its container?
like a pvnrt that couldn’t be held in glass even as a solution.
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I think you are asking here does each element have a different vaporization temperature (for a given pressure). The answer to that question is yes. If that is not your question then try again using more specific language.
Beaconator said:
Ipso defagoi the highest temp any group of elements could “sustain” is the same as the center of the earth
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No. You can heat elements to temperatures higher than the center of the sun and they will not change. The elements will ionize but they will still be the same element.
Beaconator said:
25/H^25 and so on should provide an ambient temperature?
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25 divided by hydrogen raised to the 25th power? That makes about as much sense as a soup sandwich.
 
origin said:
That makes no sense. If a sample of all the elements were placed in room, then all the elements would be at room temperature or in other words at ambient temperature.

I think you are asking here does each element have a different vaporization temperature (for a given pressure). The answer to that question is yes. If that is not your question then try again using more specific language.

No. You can heat elements to temperatures higher than the center of the sun and they will not change. The elements will ionize but they will still be the same element.

25 divided by hydrogen raised to the 25th power? That makes about as much sense as a soup sandwich.
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But then, he is barking......
 
DaveC426913 said:
No. Ambient temperature is a property of the environment - not something in the environment.


Some how I don't think you're talking about the matter states solid, liquids and gases.
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Therefore it is impossible for something in the environment to effect the ambience and we are missing some huge part of thermodynamics!

and to the second part... yes I have a one track mind
 
origin said:
That makes no sense. If a sample of all the elements were placed in room, then all the elements would be at room temperature or in other words at ambient temperature.

I think you are asking here does each element have a different vaporization temperature (for a given pressure). The answer to that question is yes. If that is not your question then try again using more specific language.

No. You can heat elements to temperatures higher than the center of the sun and they will not change. The elements will ionize but they will still be the same element.

25 divided by hydrogen raised to the 25th power? That makes about as much sense as a soup sandwich.
Click to expand...
And if I touched them would the instantly reach my body temp or would it take time?
 
exchemist said:
I'm not surprised, considering you are as mad as a box of frogs.;) I really only replied in case other readers might expect some kind of an informed response.

But I can have a go at finding you an example, if you can manage to phrase a question in an understandable way. Though it's been many years since I last did these calculations and I don't have a copy of the Rubber Book at home, with all the necessary enthalpies and entropies of formation, so I'd have to try to find the numbers on the internet.

But, whether this thread goes anywhere or not, it belongs in Chemistry, not Physics'n'Maths. I'll ask if James wants to move it.
Click to expand...
If you understood it... it wouldn’t be homework would it?
Fine sigma h^25 to 1+h^n-1 such that mass is equal....
 
origin said:
That makes no sense. If a sample of all the elements were placed in room, then all the elements would be at room temperature or in other words at ambient temperature.

I think you are asking here does each element have a different vaporization temperature (for a given pressure). The answer to that question is yes. If that is not your question then try again using more specific language.

No. You can heat elements to temperatures higher than the center of the sun and they will not change. The elements will ionize but they will still be the same element.

25 divided by hydrogen raised to the 25th power? That makes about as much sense as a soup sandwich.
Click to expand...
So basically an explosive reaction without any change in temp. Hmm wish I knew that years ago!!!! Dolts
 
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