Is the Spontaneous Reaction of Hydrogen and Oxygen Dependent on Temperature?

In summary, the conversation discusses the temperature at which the reaction between hydrogen and oxygen becomes spontaneous and the definition of spontaneity. The estimated temperature for this reaction to occur is around 530°C at standard pressure, with a Gibbs value of less than 0. The reverse reaction is prevented from happening at lower temperatures due to kinetics and thermodynamics.
  • #1
Curl
758
0
Hydrogen and Oxygen "burn"

Does anyone know the temperature at which this reaction becomes spontaneous?

2H2O--> 2H2 + O2

I can't find my book with thermodynamic data, but it should be cake for you guys.

Thanks.
 
Chemistry news on Phys.org
  • #2


Curl said:
Does anyone know the temperature at which this reaction becomes spontaneous?

2H2O--> 2H2 + O2

I can't find my book with thermodynamic data, but it should be cake for you guys.

Thanks.

What is the definition of spontaneity?
 
  • #3


The auto-ignition temperature of hydrogen in air at STP is roughly 530'C depending on concentration and what not.

sjb-2812 said:
What is the definition of spontaneity?

I think he just means at what temperature will a self-sustaining redox reaction occur.
 
  • #4


The definition of a 'spontaneous reaction' is deltaG < 0, although I think sjb-2812 might've been asking that rhetorically.

The number I get for that is about 1750 K.
 
  • #5


Thanks alxm.

I'm assuming you did this for 1atm pressure right? And how did you get the Gibbs values for the substances at those temperatures? Is it accurate to assume a linear relationship between G and temperature? Most tables I've seen offer values for 25C or so.

Also, what keeps the reverse reaction from happening at temperatures lower than this? I've seen H2 and O2 in a balloon and it didn't spontaneously react into water until a flame was brought up. What happens there? I haven't studied kinetics much, all I know is from stat mech.
 

What is the process of burning hydrogen and oxygen?

The process of burning hydrogen and oxygen is called combustion. It involves a chemical reaction between the two gases, which produces heat and water vapor as byproducts.

What is the chemical equation for the combustion of hydrogen and oxygen?

The chemical equation for the combustion of hydrogen and oxygen is 2H2 + O2 → 2H2O.

What is the energy released during the combustion of hydrogen and oxygen used for?

The energy released during the combustion of hydrogen and oxygen is primarily used to power various forms of transportation, such as cars and rockets. It is also used for electricity generation and heating.

Is the combustion of hydrogen and oxygen a sustainable source of energy?

Yes, the combustion of hydrogen and oxygen is considered a sustainable source of energy because it produces water as a byproduct and does not emit greenhouse gases or pollutants.

What are the potential dangers of handling or storing hydrogen and oxygen for combustion?

The main danger of handling and storing hydrogen and oxygen for combustion is the risk of explosion. These gases are highly flammable and must be handled with caution. Proper storage and handling techniques should be followed to ensure safety.

Similar threads

Is it possible to have an "Eternal reaction" by mixing the products?
    • Chemistry
Replies
7
Views
1K
Is Oxyhydrogen a spontaneous reaction at very high temperatures?
    • Chemistry
Replies
4
Views
3K
What influences ignition temperature and oxygen consumption
    • Chemistry
Replies
4
Views
1K
How is "always" spontaneous reconciled with equilibrium?
    • Chemistry
Replies
4
Views
2K
Methane production and storage
    • Chemistry
Replies
23
Views
2K
Complete thermal decomposition of specific compounds
    • Chemistry
Replies
4
Views
1K
Do Different Temperatures Affect Enzyme Activity in a Parabolic Arrhenius Plot?
    • Chemistry
Replies
1
Views
862
Optimizing Redox Reaction of FeO with H2
    • Chemistry
Replies
9
Views
3K
Auto ignition temperature in pure O2
    • Chemistry
Replies
8
Views
9K
A "neat set of reactions" that makes fuel on Mars
    • Chemistry
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top