Why is water which is composed of hydrogen and oxygen both flammable, not flammable?

Answer 1

Ah, it's the miracle of a chemical change. In chemistry, there are two types of changes you can observe--physical changes and chemical changes.

In a physical change, two substances are combined but each substance retains its original properties. The substances can be separated back into their component parts easily. A classic example is a combination of salt and pepper. You haven't created a new substance; you've just mixed two things together.

In a physical change, two substances are combined in such a way that they exhibit completely different chemical properties that may not resemble either of the original components. They cannot be separated by any physical means; you have to use chemistry to separate them. You have created something entirely new. An example is sodium chloride. Pure sodium is a volatile substance that is cool because it actually reacts with water, causing a fiery explosion. Chlorine is a dangerous gas. Both would be deadly if ingested. However, you combine them to create sodium chloride--your basic table salt.

Anyway, water is a completely different substance than either hydrogen or oxygen. Because of the way the atoms have bound together, there aren't electrons available to react with other substances. Because the molecule is stable, it sticks together to itself rather than breaking down into its flammable components.

Answer 2

Oxygen as I know is not flammable as it is not a fuel but it is an oxidizer which enhances combustion. You see, you breathe oxygen so that means if you lit a match the whole world would explode if you think that oxygen is flammable..

It is true that Hydrogen gas is highly flammable and will burn at concentrations as low as 4% H2 in air. When mixed with oxygen across a wide range of proportions, hydrogen explodes upon ignition.

While H2 is not very reactive under standard conditions, it does form compounds with most elements. When bonded to oxygen hydrogen can participate in a form of strong noncovalent bonding called hydrogen bonding thus producing H2O or water.

In simple explanation: when oxygen and hydrogen are mixed, they can chemically combine, generating lots of heat energy. When this reaction is complete, the product is water. So, water is what is created when hydrogen burns. We can say then in comparison that water doesn't burn because it's already an ash.♥

Answer 3

First of all, oxygen is not flammable. Oxygen is a necessary component for combustion. The more oxygen you have, the more easily and more quickly other materials will burn.

Keep in mind that whenever you start combining atoms or molecules into different compounds, the characteristics usually change significantly. For example, water (H2O) is only hydrogen and oxygen, but so is hydrogen peroxide (H2O2).

Now, if you have hydrogen gas and oxygen gas (seperate, not bonded into a compound) the combination is EXTREMELY combustible. But again, we're talking about a highly flammable material (hydrogen) surrounded by a large proportion of oxygen.

One of the great things about hydrogen engines is that when hydrogen burns (oxidizes) it is bonded to oxygen. So, the exhaust from a hydrogen engine is, essentially, water. Non-toxic, 100% safe for the environment. Talk about a clean-burning fuel!

Answer 4

Hydrogen and oxygen are both gases, of which, hydrogen is flammable. Oxygen is not flammable but it will support combustion. Both of these compound exhibit these properties in the elemental state.

Hydrogen and oxygen combine to form water where we have two hydrogen atoms bonded to the oxygen atom. This molecule will exhibit quite different properties to the elements as a result of the chemical bonds formed. This is quite typical.

Consider salt - NaCl. Sodium is silvery metal that reacts violently with water and chlorine is a green gas. But salt formed by the raction of the two is ionic in nature and has none of the properties of chlorine or sodium.

Answer 5

rhsaunder almost had it, but not quite.

What does it mean that hydrogen and oxygen are flammable together?  It means that they can combine to release energy.  Once they've done that and formed water, that energy is GONE and the flammability along with it.

It's the same story with sodium and chlorine.  Both will react violently with many things including each other (either one will react with water!) but they combine to make NaCl (table salt) which is one of the most stable compounds on earth.

Answer 6

Firemedic is correct - oxygen is necessary for combustion, but is not flammable.
You are, however correct in assuming that a MIXTURE of H2 plus O would make for a hell of a fire ball. But a COMPOUND of H2O is simply water.
When elements combine to form compounds, the characteristics of the compounds nearly always differ greatly from the individual elements.
Water is an excellent example. Rust is another - steel is magnetic, add oxygen it and it's no longer magnetic - or steel.

Answer 7

Well back in June or July there was a story about a scientist who accidentally discovered that when bombarded with certain frequency sound waves common water(may have been sea water) burns. I am amazed that it is not still in the news because it has the possibility of being a potentially limitless supply of energy. If of course more energy is extracted than is required to start the reaction in the first place

Answer 8

Because all of the flame came out when they combined. Incidentally, oxygen is not flammable -- it supports combustion.

Answer 9

Water is the product of the combustion of H2 and O2

Answer 10

It is flammable-it just vaporizes before it combusts.
Everything burns, you just have to get it hot enough.