Why are the rates of gas phase chemical reactions greater than solution phase chemical reactions?

Answer 1

A gaseous solution reacts more vigorously than a liquid or solid solution because there is a greater surface area/volume for the reactants. Basically, when you mix, for instance, gasoline fumes with oxygen, you are putting a considerably greater number of gasoline particles in direct contact with the oxygen particles that are required to form the reaction, therefore it burns much faster than liquid gasoline (the rate of burning for gasoline fumes is actually high enough to consider it an explosion, whereas liquid gasoline actually burns slow enough to sustain a flame for a considerable amount of time).

Answer 2

i think it may be because of the moleculer structure. As we know the gape of inner element in liquid phase is sufficient to react or to mixing. But in solid phase it is to close and in gas phase it is to wide, so liquid is most reactable phase.

Answer 3

The rate of reaction is far higher for liquids than solids due to the effect of surface area.

If A reacts with B then they need to touch eachother. If we have a solid cube of A and a solid cube of B then they can touch only by putting their surfaces together. However, this means that only a tiny fraction of the atoms in our cube of A are actually touching B. All of the atoms in the centre of the cube, or on other sides of the cube, are still safe.

If we put cube A into a bath of liquid cube B then things get a bit better but still, everything in the centre of cube A (most of the material) is still safely tucked away.

If we put the two powders together, things are better than before but powders don't mix well without a lot of human intervention and even then, each powder particle is actually a LOT of atoms clumped together, like with our cubes.

So what can we do? We can solubilise A and B, maybe in water, so each atom is alone in solution. Only now do A and B have full access to each other, giving a much, much faster reaction. I apologise if by 'mixture of solids' you meant a colloidal mixture, but the answer is basically the same, either way.