Want this question answered?
- because the large quantities of the powdered and combustible materials incluse two factors of increasing the reaction rate, which are more surface areas and high concentration. - And also in such these places the tempreture is high more often, so it will lead to more collision between particles and speeding up the reaction rate as well. - And the final reaction will be as an exothermic, so the energy will be released in the form of eplosion and flames.
Many common powders made in industry are combustible; particularly metals or organic materials such as flour. Since powders have a very high surface area, they can combust with explosive force once ignited. Facilities such as flour mills can be vulnerable to such explosions without proper dust mitigation efforts. Some metals become especially dangerous in powdered form, notably titanium.
You think probable to amixture of powdered materials.
There are many variables which affect the ease of combustion. The degree of mixing with the air is a very large factor. Powdered coal dust in air will ignite explosively, while lumps of coal are much harder to ignite. Different compounds have different activation energies for combustion and there require different temperatures to ignite. Sometimes combustible materials are mixed with non-combustible materials which also makes them harder to burn; for example, dry paper burns quite well, but wet paper is very difficult to burn.
Combustion is a surface process, and results from heating of the solid material. Coal is pulverized so as to give a greater surface to volume ratio, and thus burn more readily.Indeed powdered materials will sometimes combust explosively, such as explosions in flour mills.
Combustible Dusts have a KST value of Greater Than Zero, and can cause a Week to Very Strong Explosion... (Powdered Milk, Sugar, Coal, Wood, Plastic, Food/organic, Aluminum, Zirconium). Non-Combustible Dust, have a KST Value of Zero, and Don't cause an Explosion: Non-Combustible Dusts: Aggregates, such as stone, silica(sand), Silicates, Sulfates, Nitrates, Carbonates, Phosphates, Portland cement, Sand, Limestone.
It is more simple to dissolve or to refine powdered materials.
If the rain water contain powdered materials the mixture is nonhomogeneous.
The lead in a pencil is mostly a mixture of powdered graphite and clay.
A ladle is used in laboratry to transfer small amounts af powdered or granular materials.
Filters from paper, ceramics, glass, textiles, plastics, powdered or granulated materials, active carbon, etc.
If the rain water contain powdered materials the mixture is nonhomogeneous.