magnesium and hcl

[slacking20]

I just want to ask why heat is released in a reaction between magnesium and hcl.

[woelen]

The combo Mg/HCl has a higher energy content than the combo Mg(2+)/H2/Cl(-). The energy is in the Mg-metal. The idea behind this is not different from the idea behind burning of combustible materials, only the amount of heat involved is a little bit less.

 

Any chemical reaction involves heat. A reaction, which produces heat is called exothermic and a reaction which takes heat is called endothermic. An endothermic reaction usually does not occur spontaneously, one has to put effort in it. The products of such a reaction have a higher energy content than the initial materials.

[RyanJ]

Woelen, could it be said that in an exothermic reaction such as this one the reactants "try to move" into a more stable forms, in the change over the energy difference between the reactants and the products is the heat loss, [math]\Delta H[/math]?

 

If correct then the reverse could be said for the endothermic reactions, the prodcuts are actually energetically less table the the reactants as they have taken in energy from the environment and gained energy...

 

Cheers,

 

Ryan Jones

[Neil9327]

The combo Mg/HCl has a higher energy content than the combo Mg(2+)/H2/Cl(-). The energy is in the Mg-metal. The idea behind this is not different from the idea behind burning of combustible materials' date=' only the amount of heat involved is a little bit less.

 

Any chemical reaction involves heat. A reaction, which produces heat is called exothermic and a reaction which takes heat is called endothermic. An endothermic reaction usually does not occur spontaneously, one has to put effort in it. The products of such a reaction have a higher energy content than the initial materials.[/quote']

 

Woelen: Apologies if you've been asked this before, but what chemical reaction is taking place in the container in your avatar picture? It looks both quite cool and quite spooky at the same time.

[woelen]

@RyanJ: Informally speaking you are right. When a compound looses energy, it moves towards a more stable form, while heat and/or light is released. On the other hand, putting energy in compounds can transform them to a less stable compound or set of compounds.

 

@Neil9327: This is a reaction, described on my website:

http://woelen.scheikunde.net/science/chem/exps/Fe+HNO3+Gimp/index.html

[RyanJ]

@RyanJ: Informally speaking you are right. When a compound looses energy, it moves towards a more stable form, while heat and/or light is released. On the other hand, putting energy in compounds can transform them to a less stable compound or set of compounds.

 

 

Yea... the equilibrium for the reaction would shift to try to counter act the change... so when the equilibrium is exothermic in its forward direction and takes up energy in the reverse reaction as it tried to counter act the change to the system... its actually pretty facinating

 

Cheers,

 

Ryan Jones

[encipher]

What is mean by gimp on that link woelen? The only gimp i know is the image editing software =D

[RyanJ]

What is mean by gimp on that link woelen? The only gimp i know is the image editing software =D

 

Thats exactly what it was as far as I remember... Think I saw it here.

 

Cheers,

 

Ryan Jones

[encipher]

I can't beleive I didn't make that out the first time I read it through..

 

Excessive exposure to Gimp may lead to problems with the muscles. For left-handed people the left arm and shoulder are most vulnerable, for right-handed people the right arm and shoulder are most vulnerable.

 

Haha, That was a dead giveaway, I can't beleive I didn't notice that the first time.

 

Thanks RyanJ