Why doesn't water burn? its made from HYDROGEN (highly flammable) and OXYGEN (fuel for fire)?!?

Answer 1

The hydrogen has already been completely burnt by the oxygen. It can't burn any more. It is no longer hydrogen and oxygen. It is a waste product of burnt hydrogen and oxygen.

Answer 2

You're thinking about it in the wrong way. When we burn something you are giving the environment enough energy for a reaction to take place. A reaction depends of the molecular structure of the compounds in question. Thus oxygen. In a latent state oxygen on it's own with no fire will just whizz about. As soon as you introduce a spark or flame, you give the vicinty around the flame energy and the oxygen atoms will use this energy to reconfigure themselves into a lower energy state (which sounds contradictory).

Same with hydrogen or any other compound. Take coal, you burn it and you release carbon dioxide. The process of combining oxygen with carbon produces a molecule which is inherantly more stable than oxygen alone so in this state energy is release when the two combine via a reaction and (heat is this given off).

So lets take water and petrol. Water is a very stable compound and even if you heat it or put a blow torch to it, it won't react or bun because it's state is energy efficient, there is no other state it could possibly go to which would be of lower energy. I'm no chemist but if you were to find a gas which binded to oxygen or hydrogen more strongly than they binded each other then a reaction would occur.

With petrol the binding of oxygen to one of the carbon atoms or the hydrogen atoms prodcuces much more stable compounds (H20, CO2, CO etc) and as such explosions will take place since and explosion is just a release of energy from one state to a lower energy state

i hope that makes sense

Answer 3

Burning is the combination of a material with oxygen. Water is already a compound of hydrogen combined with oxygen. Oxygen is not the fuel, but the element necessary for burning.The hydrogen is the fuel.Water is a more stable condition than either oxygen or hydrogen separately.

Answer 4

Actually, oxygen is an oxidizer. Why doesn't salt kill you? Salt is Na, a highly reactive, volatile metal and Cl is a poisonous gas. It's because it's in crystalline form and the bonds that hold it together are tough to break. The same with water. When you combine these 2 elements the resulting molecule has completely different properties.

Answer 5

Because elements such as hydrogen and oxygen adopt completely different properties when they are combined into compounds.

In this case, the two highly reactive chemicals of hydrogen and oxygen have reacted together to form a much more stable and un-reactive compound, water. In effect their "reactivity" has been "used up" already so water has very little "reactivity" left.

Answer 6

When hydrogen and oxygen chemically combine - the product (water) loses the characteristics of H2 and O2. It's no longer a gas, either.

Another example... when Sodium and a poisonous gas (Chlorine) chemically combine, it becomes table salt. (and it's no longer poisonous)

Answer 7

The reason is simple: Water is a COMPOUND. A compound is a substance that are chemically bonded together, and the properties of a compound is entirely defferent from the elements in which it is made from.

2H2 + O2 ---> 2H2O

Hence the properties of water is different from its elements: H2 and O2

Answer 8

Water is hydrogen which has already been burnt. You could liken it to hydrogen being coal, oxygen being oxygen, and water being ash - you can't burn the ash!

Answer 9

Yeh i wondered this. Considering when you split the two, like in the experimental car engines, they become flammable again

Answer 10

Water is the result of the two elements bonding, changing the original structure of the two elements permanently.