# Is Oxyhydrogen a spontaneous reaction at very high temperatures?

1. Apr 13, 2014

### ineedaquickie

Hi, this may seem like a noob question for you geeks out there, but I cant wrap my head around this.
The formula for a spontaneous reaction is $\Delta$H-T$\Delta$S < 0
Basically, since the reaction between hydrogen and oxygen gas has a negative change in enthalpy it must mean that if the temperature in Kelvin is big enough then the reaction between oxygen and hydrogen gas will not be spontaneous.

Because the negative T multiplied with the negative change in entrophy will be more positive than the enthalpy change and it wont be a spontaneous process? right?

2. Apr 13, 2014

### Ygggdrasil

3. Apr 13, 2014

### ineedaquickie

Ill read up on this, thanks.

4. Apr 17, 2014

### ineedaquickie

I'm sorry to bring this up, but does the same count for the burning of magnesium. Burning of magnesium is exothermic, but the change in entropy is negative as well so if the temp is big enough, the reaction wont be spontaneous. Correct?

5. Apr 17, 2014

### Ygggdrasil

Yes, that's correct.

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted